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Bihar Board 12th Maths Model Papers

Bihar Board 12th Maths Model Question Paper 1 in English Medium

Time : 3 Hours 15 Min
Full Marks: 100

Instructions for the candidates :

1. Candidates are required to give their answers in their own words as far as practicable.
2. Figure in the right-hand margin indicates full marks.
3. While answering the questions, the candidate should adhere to the word limit as far as practicable.
4. 15 Minutes of extra time has been allotted for the candidate to read the questions carefully.
5. This question paper is divided into two sections. Section-A and Section-B
6. In Section A, there are 1-50 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with blue/black ball pen against the correct option on the OMR Sheet provided to you. Do not use Whitener/Liquid/ Blade/Nail on OMR Sheet otherwise result will be invalid.
7. In section-B, there are 25 short answer type questions (each carrying 2 marks), out of which only 15 (fifteen) questions are to be answered.
   A part from this there is 08 Long Answer Type questions (each carrying 5 marks), out of which 4 questions are to be answered.
8. Use of any electronic device is prohibited.

Objective Type Questions

There are 1 to 50 objective type questions with 4 options, choose the correct option which, is to be answered on OMR Sheet. (50 x 1 = 50)

Question 1.
Which of the following has its inverse function one-one and onto?
(a) one-one onto
(b) one-one into
(c) many one onto
(d) many on into
Answer:
(a) one-one onto

Question 2.
A relation R in a set X is an equivalence relation if R is
(a) reflexive
(b) symmetric
(c) transitive
(d) All of above
Answer:
(d) All of above

Question 3.
The number of all one-one functions from set {a, b, c, d} to itself is
(a) 12
(b) 24
(c) 36
(d) None
Answer:
(b) 24

Question 4.
If \(-\frac{\pi}{2}<x<\frac{\pi}{2}\) then tan(tan^-1 x) =
(a) tan x
(b) cotx
(c) x
(d) -x
Answer:
(c) x

Question 5.
Sin^-1 x + Cos^-1 y =
(a) 0
(b) \(\frac{\pi}{4}\)
(c) \(\frac{\pi}{2}\)
(d) π
Answer:
(c) \(\frac{\pi}{2}\)

Question 6.
If x > 0, y > 0, xy < 1, then tan^-1x + tan^-1 y =
(a) tan^-1 (x+y)
(b) \(\tan ^{-1} \frac{x+y}{1-x y}\)
(c) tan^-1
(d) sin^-1(x + y)
Answer:
(b) \(\tan ^{-1} \frac{x+y}{1-x y}\)

Question 7.
(a) tan^-12x
(b) \(\tan ^{-1} \frac{2 x}{1-x^{2}} \)
(c) \(\tan ^{-1} \frac{2 x}{1+x^{2}}\)
(d) \(\cot ^{-1} \frac{2}{x}\)
Answer:
(b) \(\tan ^{-1} \frac{2 x}{1-x^{2}} \)

Question 8.
\(2\left[\begin{array}{ll}
x & y \\
1 & m
\end{array}\right]\) =

Answer:
(c) \(\left[\begin{array}{cc}
2 x & 2 y \\
1 & 2 m
\end{array}\right]\)

Question 9.
\(5\left|\begin{array}{ll}
2 & 3 \\
3 & 4
\end{array}\right|=\)

Answer:
\(\left|\begin{array}{cc}
2 & 3 \\
15 & 20
\end{array}\right|\)

Question 10.
If A = \(\left[\begin{array}{cc}
5 & -5 \\
5 & -5
\end{array}\right]\) then A’ =

Answer:
(c) \(\left[\begin{array}{cc}
5 & 5 \\
-5 & -5
\end{array}\right]\)

Question 11.
\(\left|\begin{array}{ll}
1 & 0 \\
0 & 1
\end{array}\right|=\)
(a) 0
(b) 1
(c) -1
(d) 2
Answer:
(b) 1

Question 12.
\(\left[\begin{array}{ll}
\mathbf{a} & \mathbf{b} \\
\mathbf{c} & \mathbf{d}
\end{array}\right]+\left[\begin{array}{ll}
\mathbf{p} & \mathbf{q} \\
\mathbf{r} & \mathbf{s}
\end{array}\right]=\)

Answer:
\(\left[\begin{array}{cc}
a+p & b+q \\
c+r & d+s
\end{array}\right]\)

Question 13.
For a non-invertible matrix A,
(a) | A | = 0
(b)|A|≠ 0
(c) | A | = 1
(d) | A | = 2
Answer:
(b)|A|≠ 0

Question 14.
If 1 is an unit matrix of order 2 × 2 then I³ =
(a) 3I²
(b) 3 + I
(c) 3I
(d) I
Answer:
(d) I

Question 15.
If A = \(\left[\begin{array}{ll}
2 & 3 \\
4 & 5
\end{array}\right]\) and \(\left[\begin{array}{ll}
4 & 6 \\
8 & 10
\end{array}\right]\) then 2A – B =
(a) [0]
(b) [0,0]
(c) \(\left[\begin{array}{ll}
0 & 0 \\
0 & 0
\end{array}\right]\)
(d) [3]
Answer:
(c) \(\left[\begin{array}{ll}
0 & 0 \\
0 & 0
\end{array}\right]\)

Question 16.
If the order of two matrices A and B are 2×4 and 3×2 respectively then the order of AB is
(a) 2 x 2
(b) 4 x 3
(c) 2 x 3
(d) it is not possible to find AB
Answer:
(d) it is not possible to find AB

Question 17.
\(\frac{d}{d x}(\tan x)=\) =
(a) cot x
(b) Sec²x
(c) Secx tanx
(d) Secx
Answer:
(b) Sec²x

Question 18.
\(\frac{d}{d x}\left(\sin ^{3} x\right)=\)
(a) 3 cos³
(b) 3 sin²xcosx
(c) 3sin²x
(d) cos³x
Answer:
(b) 3 sin²xcosx

Question 19.
\(\frac{d}{d x}\) [3 (sin² x + cos²x )] =
(a) 3
(b) 1
(c) 0
(d) 6 sin x cos x
Answer:
(c) 0

Question 20.
\(\frac{d}{d x}\) (e^4x) =
(a) e^4x
(b) e^x
(c) \(\frac{e^{4 x}}{4}\)
(d) 4e^4x
Answer:
(d) 4e^4x

Question 21.
\(\frac{d}{d x}\left(x^{5}\right)=\)
(a) 5x⁵
(b) 5x⁴
(c) \(\frac{x^{6}}{6}\)
(d) \(\frac{x^{4}}{4} \)
Answer:
(b) 5x⁴

Question 22.
\(\frac{d}{d x}\) [log(x³)] =
(a) \(\frac{1}{x^{3}}\)
(b) \(\frac{3}{x}\)
(c) 3x
(d) \(\frac{3}{x^{3}}\)
Answer:
(b) \(\frac{3}{x}\)

Question 23.
If x= cosθ,y = sinθ then \(\frac{d y}{d x}\) =
(a) tanθ
(b) sec²θ
(c) cotθ
(d) – cotθ
Answer:
(d) – cotθ

Question 24.
\(\frac{d}{d x}\left(x^{1 / 3}\right)=\)

Answer:
(d) \(\frac{1}{3} x^{2 / 3}\)

Question 25.
∫ sin 2x dx =
(a) K + 2 cos2x
(b) \(\frac{\cos 2 x}{2}+K\)
(c) \(K-\frac{\cos 2 x}{2}\)
(d) \(K-\frac{\cos 2 x}{3}\)
Answer:
(c) \(K-\frac{\cos 2 x}{2}\)

Question 26.
∫x⁴dx =
(a) K + x⁵
(b) \(K+\frac{x^{4}}{5}\)
(c) \(K+\frac{x^{5}}{5}\)
(d) \(K+\frac{x^{5}}{4}\)
Answer:
(c) \(K+\frac{x^{5}}{5}\)

Question 27.
∫e^3x dx =
(a) e^3x + K
(b) K + 3e^3x
(c) \(\frac{e^{3 x}}{3}+K\)
(d) \(\frac{e^{3 x}}{4}+K\)
Answer:
(c) \(\frac{e^{3 x}}{3}+K\)

Question 28.
\(\int \frac{3}{x} d x=\)
(a) K + 3x²
(b) \(K-\frac{3}{x^{2}}\)
(c) 3x + K
(d) K + 3 log|x|
Answer:
(d) K + 3 log|x|

Question 29.
∫3dx =
(a) 3 + K
(b) x + K
(c) 3x + K
(d) 3K
Answer:
(c) 3x + K

Question 30.
∫√x.dx =

Answer:
(c) \(\frac{2}{3} x^{3 / 2}+K\)

Question 31.
\(\int_{0}^{\pi / 2} \sin x d x=\)
(a) 0
(b) 1
(c) -1
(d) \(\frac{\pi}{2}\)
Answer:
(b) 1

Question 32.
\(\int_{0}^{1} e^{x} d x=\)
(a) e
(b) e + 1
(c) e – 1
(d) 2e
Answer:
(c) e – 1

Question 33.
The solution of the equation \(\frac{d x}{x}=\frac{d y}{y}\) is
(a) x = Ky
(b) xy = K
(c) x + y = K
(d) x – y = K
Answer:
(a) x = Ky

Question 34.
The solution of the differential equation cosx dx + cosy dy = 0 is
(a) sinx + cosy = K
(b) sinx + siny = K
(c) cosx + cosy = K
(d) None of these
Answer:
(b) sinx + siny = K

Question 35.
The solution of e^xdx + e^ydy = 0
(a) e^x + e^y= K
(b) e^x – e^y = K
(c) e^x+y = K
(d) None of these
Answer:
(a) e^x + e^y= K

Question 36.
The integrating factor of the linear differential equation \(\frac{d y}{d x}+x y=x^{3}\) is
(a) e^x
(b) \(e^{\frac{x^{2}}{2}}\)
(c) x
(d) None of these
Answre:
(b) \(e^{\frac{x^{2}}{2}}\)

Question 37.
∫ logdx =
(a) x log x – x + K
(b) x log x + x + K
(c) \(\frac{1}{x}+K\)
(d) \(\frac{1}{2}(\log x)^{2}+K\)
Answer:
(a) x log x – x + K

Question 38.
\(\int \frac{d x}{1+x^{2}}=\)
(a) tan^-1 x + K
(b) sin^-1 x + K
(c) cos^-1 x + K
(d) cot^-1 x + K
Answer:
(a) tan^-1 x + K

Question 39.
\(\overrightarrow{| \vec{i}} |=\)
(a) 0
(b) 1
(c) 2
(d) 3
Answer:
(b) 1

Question 40.
\(\vec{i} \cdot \vec{i}=\)
(a) 0
(b) 1
(c) \(\vec{j}\)
(d) \(\vec{k}\)
Answer:
(b) 1

Question 41.
\(\vec{i} \times \vec{i}=\)
(a) \(\vec{i}\)
(b) \(\vec{0}\)
(c) \(\vec{j}\)
(d) \(\vec{k}\)
Answer:
(b) \(\vec{0}\)

Question 42.
If O is the origin and the position vector of a point(2,3,4) then \(\overrightarrow{\mathrm{OA}}=\)

Answer:
(b) \(2 \vec{i}+3 \vec{j}+3 \vec{k}\)

Question 43.
\(\overrightarrow{| i}+2 \vec{j}+3 \vec{K} |=\)
(a) 14
(b) 6
(c) 1
(d) √14
Answer:
(d) √14

Question 44.
\((2 \vec{i}-3 \vec{j}+4 \vec{k}) \cdot(3 \vec{i}+4 \vec{j}-5 \vec{k})=\)
(a) 14
(b) -14
(c) 26
(d) -26
Answer:
(d) -26

Question 45.
The direction cosines of the y-axis are
(a) 0, 0, 0
(b) 1, 0, 0
(c) 0, 1, 0
(d) 0, 0, 1
Answer:
(c) 0, 1, 0

Question 46.
The condition for two lines having direction cosines I₁ m₁,n₁ and I₂, m₂, n₂ being parallel is
(a) l₁l₂ + m₁m₂ + n₁n₂ = 0
(b) \(\frac{I_{1}}{I_{2}}+\frac{m_{1}}{m_{2}}+\frac{n_{1}}{n_{2}}=0\)
(c) \(\frac{I_{1}}{I_{2}}=\frac{m_{1}}{m_{2}}=\frac{n_{1}}{n_{2}}\)
(d) None of these
Answer:
(c) \(\frac{I_{1}}{I_{2}}=\frac{m_{1}}{m_{2}}=\frac{n_{1}}{n_{2}}\)

Question 47.
The equation of a plane parallel to the plane x + 2y + 3z + 5 = 0 is
(a) x + 2y + 3z + 5 = 0
(b) x – 2y + 3z + 5 = 0
(c) x + 2y – 3z + 5 = 0
(d) None of these
Answer:
(d) None of these

Question 48.
The equation of a plane parallel to yz-plane is
(a) x + K
(b) y = K
(c) z = K
(d) None of these
Answer:
(a) x + K

Question 49.
If A and B be two arbitrary events where A ≠ φ then P (A∩B) =
(a) P (A). P (B/A)
(b) P (A) + P (B/A)
(c) P (A) – P (B/A)
(d) None of these
Answer:
(a) P (A). P (B/A)

Question 50.
The function in a linear programming problem whose maximum or minimum value has to be determined is called
(a) Objective function
(b) Constraint
(c) Both (a) and (b)
(d) None of these
Answer:
(a) Objective function

Non-Objective Type Questions

Short Answer Type Questions

Question No. 1 to 25 are short answer type questions. Each question of this category carries 2 marks. Answer any 15 questions. (15 x 2 = 30)

Question 1.
Examine whether the function f: R → R is one-one or many-one where f (x) = | x |, x ∈ R
Answer:
We have f(-1) = |- 1| = 1 and f(-1) = | 1 | = 1
Thus two different elements in R have the same Image,
∴ f is not one-one function, f is many one function.

Question 2.
Prove that 2 \(\tan ^{-1} \frac{1}{5}+\tan ^{-1} \frac{1}{4}=\tan ^{-1} \frac{32}{43}\)
Answer:

Question 3.
Solve for x : cot^-1 x + sin ^-1\(\frac{1}{\sqrt{5}}\) = \(\frac{\pi}{4}\)
Answer:

Question 4.
Find the value of x from the following
\(\left[\begin{array}{cc}
2 x-y & 5 \\
3 & y
\end{array}\right]=\left[\begin{array}{cc}
6 & 5 \\
3 & -2
\end{array}\right]\)
Answer:
Given that \(\left[\begin{array}{cc}
2 x-y & 5 \\
3 & y
\end{array}\right]=\left[\begin{array}{cc}
6 & 5 \\
3 & -2
\end{array}\right]\)
∴ 2x – y = 6 ………..(1)
y = -2………..(2)
from (i) 2x + 2 = 6 ⇒ 2x = 4. ∴ x = 2
∴x = 2, y = 2

Question 5.
Evaluate:
\(\left|\begin{array}{ccc}
16 & 9 & 7 \\
23 & 16 & 7 \\
32 & 19 & 13
\end{array}\right|\)
Answer:

Question 6.
When Evaluate x : \(\left|\begin{array}{ll}
x & 4 \\
2 & 2 x
\end{array}\right|=0\)
Answer:
Given that \(\left|\begin{array}{ll}
x & 4 \\
2 & 2 x
\end{array}\right|=0\)
⇒ 2x² – 8 = 0
⇒ 2x² = 8
⇒ x² = 4
∴ x = ±2

Question 7.
If A = \(\left[\begin{array}{c}
2 \\
-4 \\
3
\end{array}\right]\) and B = [ 2 3 4] then find B’A’
Answer:

Question 8.
If y + x = sin (y +x) then find dy/dx
Answer:

Question 9.
If \(y=\log \left(x^{2} \sqrt{x^{2}+1}\right)\) then find \(\frac{d y}{d x}\)
Answer:

Question 10.
If x = a cosθ, y = b sinθ, then find dy/dx
Answer:
Given that x = acosθ
D.W.R. to θ \(\frac{d x}{d \theta}\) = -asinθ…(i)
and y = bsinθ
D.w.r. to θ ; \(\frac{d y}{d \theta}\) = bcosθ …(ii)
\(\frac{(\mathrm{ii})}{(\mathrm{i})} \frac{d y}{d x}=-\frac{b}{a} \cot \theta\)

Question 11.
Integrate ∫ (sin x +cos x)²dx.
Answer:
Let I = ∫ (sin x + cos x)² dx
= ∫ (sin²x + cos²x + 2sinx-cosx)dlv
= ∫ (l + sin 2x)clx = ∫ dx + ∫ sin 2x dx
= \(x-\frac{\cos 2 x}{2}+c\)

Question 12.
Evaluate: \(\int_{0}^{\pi / 2} \frac{d x}{1+\sin x}\)
Answer:

Question 13.
Evaluate : \(\int_{0}^{\pi / 2} \frac{\sin x d x}{\sin x+\cos x}\)
Answer:

Question 14.
Solve \(\frac{d y}{d x}\) – y tanx =-ysec²x.
Answer:
Given differentia] Equation is \(\frac{d y}{d x}\) – y tanx =-ysec²x.
This is L.D.E. of the form \(\frac{d y}{d x}\) + Py = Q
Here p = – tan x Q = sec²x

∴ Solution of given diff. eqn. is
y x l.F.= ∫ Q-(lF)dx + C
⇒ ycosx = ∫sec²x.cosxdx + C
⇒ ycosx = ∫ secxdx + C
⇒ ycosx = log |secx + tanx| + C
This is requried solution of given diff. eqn.

Question 15.
Integrate : ∫x²e^xdx
Answer:
Let I = ∫x²e^xdx

Question 16.
Find the scalar product of \(\overrightarrow{5} \vec{i}+\vec{j}-3 \vec{k}\) and \(3 \vec{i}-\overrightarrow{4 j}+7 \vec{K}\)
Answer:
Let \(\vec{a}=5 \hat{l}+\hat{j}-3 \hat{k}\) and \(\vec{b}=3 \hat{\imath}-4 \hat{j}-7 \hat{k}\)
∴ \(\vec{a} \cdot \vec{b}\) = (5 x 3) + (1 x -4)÷(- 3 x 7)
15 – 4 – 21 = – 10

Question 17.
If \(\vec{a}=3 \vec{i}+4 \vec{j}-5 \vec{k}\) and b = \(7 \vec{i}-3 \vec{j}+6 \vec{K}\) then find \((\vec{a}+\vec{b}) \times(\vec{a}-\vec{b})\)
Answer:

Question 18.
Find the acute angle between two straight lines whose direction ratios are (1,1,0) and (2,1,2).
Answer:
Direction ratios of the first line are 1,1,0
∴Its direction cosines are

Direction ratios of the second line are 2,1,2
its direction cosines are

Question 19.
Find the values of p so that the lines \(\frac{11-x}{p}=\frac{3 y-3}{2}=\frac{17-z}{5}\) and
\(\frac{x-22}{3 p}=\frac{2 y-7}{27 p}=\frac{z-100}{6 / 5}\) are perpendicular to each other.
Answer:


⇒ -3p² + 9p – 6 = 0
⇒ 3p² – 9p + 6 = 0
⇒ p² – 3p + 2 = 0
⇒ p² – 2p – p + 2 = 0
⇒ p(p – 2) -1 (p – 2) =0
⇒ (p – 2) (p – 1) = 0
∴ p = 2, 1

Question 20.
Prove that the two planes, 3x – 4y + 5z = 0 and 2x – y – 2z = 5 are mutually perpendicular.
Answer:
Given equations of plane are 3x – 4y + 5z = 0 …(i)
and 2x-y-2z = 5 …(ii)
Here a₁= 3 b₁= – 4, c₁ = 5; a₂ = 2, b₂ = -1 c₂=- 2
a₁a₂ + b₁b₂ + c₁c₂; 6 + 4 – 10 = 0
Since product of Direction’ratios at two planes are zero, plane (i) & (ii) are perpendicular.

Question 21.
What is the probability of occurrence of a number greater than 2 if it is known that only even num¬bers can occur ?
Answer:
Let S = {1,2,3,4,5,6}; A = {2,4,6}
B= {3, 4, 5,6}

Question 22.
A person tosses a coin 3 times. Find the probability of occurrence of exactly one head.
Answer:
Let p = Probability of getting a head in one trial

Question 23.
If y = sin x + cosx, then find \(\frac{d^{2} y}{d x^{2}}\)
Answre:
Given that y = sinx + cosx; D.w.r. to x both sides
∴ \(\frac{d y}{d x}\) = cps x – sin x, Again D.w.r.to x both sides
⇒ \(\frac{d^{2} y}{d x^{2}}\) = – sin x – cosx (sinx + cosx)

Question 24.
Find the values of \(\left|\begin{array}{lll}
a & a^{2} & a^{3} \\
b & b^{2} & b^{3} \\
c & c^{2} & c^{3}
\end{array}\right|\)
Answer:

Question 25.
If A and B be two events and 2P (A) = P (B) = 6/13 and P (A/B) = 1/3, then find (P(A ∪ B)
Answer:

Long Answer Type Questions

Question no. 26 to 33 are long answer type questions. Each question carries 5 marks.
Answer any 4 questions out of these. (4 × 5 = 20)

Question 26.
If y = \(e^{x^{x}}\) then find \(\frac{d y}{d x}\)
Answer:

Question 27.
Prove that sinθ (1 + cosθ)has maximum value at θ = \(\frac{\pi}{3}\)
Answer:
Let y = sinθ(1 + cosθ)
D .w.r. to 0 both sides

Question 28.
Evaluate : \(\int_{0}^{\pi} \frac{x}{1+\sin x} d x\)
Answer:

Question 29.
Solve: (x² + y2)\(\frac{d y}{d x}\) = 2xy
Answer:
Given differential equ. is (x² + y2)\(\frac{d y}{d x}\) = 2xy

This is Homogeneons diff. equation put y = vx

Question 30.
Maximize : Z = 50x + 15y
subject to : 5A + y ≤ 5, x + y ≤ 3 and x, y ≥ 0
Answer:
Its corresponding equation
5x + y = 5 …… (i)
x + y = 3 ……..(ii)

Question 31.
A speaks the truth in 75% casses and B in 80% of the cases. In what percentage of cases are they likely to contradict each other in stating the same fact ?
Answer:
Let E = The Event of A speaking the truth and F = The Event of B speaking the truth.
Then P(E) = \(\frac{75}{100}=\frac{3}{4}\) and P(F) = \(\frac{80}{100}=\frac{4}{5}\)
Required probability P(A & B contradicting each other)
= P(EF̄) or ĒF) = P(EF̄+ĒF)= P(E)- P(F̄) + P(Ē).P(F)
= P(E) .[1 – P(F)]+[1 – P(E). P(F)]
∴ A &.B are likely to contradict each other in 35% cases.

Question 32.
Find the acute angle between the straight line \(\frac{x}{1}=\frac{y}{3}=\frac{z}{0}\) and plane 2x + y = 5
Answer:
Given that \(\frac{x}{1}=\frac{y}{3}=\frac{z}{0}\) and 2x + y = 5
Here a₁, b₁, c₁ & a₂ = 2, b₂= 1, c₂ = 0
∴ Acute angle between the given line and plane is

Question 33.
Factorize. \(\left|\begin{array}{ccc}
(b+c)^{2} & a^{2} & a^{2} \\
b^{2} & (c+a)^{2} & b^{2} \\
c^{2} & c^{2} & (a+b)^{2}
\end{array}\right|\)
Answer:

Bihar Board 12th Economics Model Papers

Bihar Board 12th Economics Model Question Paper 1 in English Medium

Time : 3 Hour 15 Min
Full Marks : 100

Instructions

1. Candidates are required to give their answers in their own words as far as practicable.
2. Figures in the right hand margin indicate full marks.
3. 15 minutes of extra time has been allotted for the candidate to read the questions carefully.
4. This question paper has two sections : Section-A and Section-B.
5. In Section-A, there are 50 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with black/blue ball pen against the correct option on OMR Sheet provided to you Do. not use Whitener/Liquid/Blade/Nail on OMR Sheet, otherwise the result will be treated as invalid.
6. In Section-B, there are Non-objective type questions. There are 25 Short answer type questions, out of which any 15 questions are to be answered. Each question carries 2 marks. Apart froms this, there are 08 Long answer type questions, out-of which any 04 of them are to be answered. Each questions carries 5 marks.
7. Use of any electronic device is prohibited.

Objective Type Questions

Questions no. 1 to 50 have four options provided out of which only one is correct. You have to mark, your selected option, on the OMR-Sheet. Each question carries 1 (one) marks.

Question 1.
Production Possibility curve is :
(a) Concave to the axis
(b) Convex to the axis
(c) Parallel to the axis
(d) Vertical to the axis
Answer:
(a) Concave to the axis

Question 2.
Which one is the limitation of Macro Economics ?
(a) Collective Economic
(b) Paradox
(c) Both A and B
(d) None of these
Answer:
(c) Both A and B

Question 3.
How we calculate marginal utility ?
(a) \(\frac { ΔMU }{ ΔQ }\)
(b) \(\frac { ΔTU }{ ΔQ }\)
(c) \(\frac { ΔQ }{ ΔTU }\)
(d) \(\frac { ΔQ }{ ΔMU }\)
Answer:
(b) \(\frac { ΔTU }{ ΔQ }\)

Question 4.
Who propounded the ordial utility theory ?
(a) Marshall
(b) Pigou
(c) Recardo
(d) Hicks & Allen
Answer:
(d) Hicks & Allen

Question 5.
The quantity of goods which the seller is ready to sell in a market at fixed price and time is called.
(a) Supply
(b) Demand
(c) Elasticity of supply
(d) Elasticity of Demand
Answer:
(a) Supply

Question 6.
Which is a reason of change in demand ?
(a) Change of consumer’s income
(b) Change in price of related goods
(c) Population Increase
(d) All of these
Answer:
(d) All of these

Question 7.
For Giffin goods, price elasticity of demand is :
(a) Negative
(b) Positive
(c) Zero
(d) None of these
Answer:
(b) Positive

Question 8.
Production function is expressed as :
(a) QX = PX
(b) QX = DX
(c) QX = f (A,B,C,D)
(d) None of these
Answer:
(c) QX = f (A,B,C,D)

Question 9.
Which of the following is not fixed cost ?
(a) Cost of raw materials
(b) Rent of the factory
(c) Interest
(d) Insurance Premium
Answer:
(a) Cost of raw materials

Question 10.
Which of the following is true ?
(a) TVC = TC – TFC
(b) TC = TVC – TFC
(c) TFC = TVC – TC
(d) TC = TVC × TFC
Answer:
(a) TVC = TC – TFC

Question 11.
In which market MR may become zero or negative ?
(a) Monopoly
(b) Monopolistic competition
(c) Both A and B
(d) Perfect competition
Answer:
(c) Both A and B

Question 12.
In perfect competition :
(a) AR = MR
(b) AR > MR
(c) AR < MR
(d) AR + AC = MR
Answer:
(a) AR = MR

Question 13.
The basic condition of a firm’s equillibrium is :
(a) MR = AR
(b) MC > MR
(c) MR < TR
(d) AC = AR
Answer:
(b) MC > MR

Question 14.
If the price of goods rises by 20% and supply increases by 40%, then the supply of such goods will be :
(a) Elastic
(b) Inelastic
(c) Highly Elastic
(d) Perfectly Elastic
Answer:
(d) Perfectly Elastic

Question 15.
Which one of the following is true for monopoly.
(a) Firm is price-maker
(b) Demand curve slops downward
(c) Price discrimination Possibility arises
(d) All of the above
Answer:
(d) All of the above

Question 16.
Who gave the concept of ‘Time Element’ in price determination process ?
(a) Ricardo
(b) Walras
(c) Marshall
(d) J.K. Mehta
Answer:
(c) Marshall

Question 17.
Which is the component of factor price determination ?
(a) Rent
(b) Wages
(c) Interest
(d) All of the above
Answer:
(d) All of the above

Question 18.
The elasticity of a straight line supply curve originating from the centre of origin is
(a) Less than unit
(b) Greater than unit
(c) Equal to unit
(d) Equal to Zero
Answer:
(c) Equal to unit

Question 19.
The alternative name of opportunity cost is :
(a) Equilibrium Price
(b) Economic Cost
(c) Marginal Cost
(d) Average Cost
Answer:
(b) Economic Cost

Question 20.
What happens when production is shut down ?
(a) Variable costs become zero
(b) Fixed costs increases
(c) Variable costs decline
(d) Fixed costs become zero
Answer:
(a) Variable costs become zero

Question 21.
A curve which rises first and starts declining after that is called :
(a) APP
(b) MPP
(c) TPP
(d) All these
Answer:
(d) All these

Question 22.
An active factor of production is :
(a) Capital
(b) Labour
(c) Land
(d) None of these
Answer:
(c) Land

Question 23.
Which of the following is the main reason of operating the Law of Dimishing Returns ?
(a) Scarcity of factors
(b) Imperfect Substitution between Factors
(c) Both A and B
(d) None of these
Answer:
(c) Both A and B

Question 24.
Average variable costs is :
(a) TVC × Q
(b) TVC + Q
(c) TVC – Q
(d) TVC ÷ Q
Answer:
(d) TVC ÷ Q

Question 25.
“Supply creates its own demand”. Who propounded this law ?
(a) J.B. Say
(b) J.S. Mill
(c) Keynes
(d) Ricardo
Answer:
(a) J.B. Say

Question 26.
With increase in investment, MEC :
(a) Rises
(b) Falls
(c) Remains Constant
(d) None of these
Answer:
(b) Falls

Question 27.
Increase in aggregate demand of equilibrium level of income and employment causes increase in :
(a) Employment
(b) Production
(c) Income
(d) All of the above
Answer:
(d) All of the above

Question 28.
Which one is correct ?
(a) A.K = \(\frac { 1 }{ MPc }\)
(b) B.K = \(\frac { 1 }{ MPc }\)
(c) C.K = \(\frac { 1 }{ 1-MPc }\)
(d) D.K = \(\frac { 1 }{ 1+MPs }\)
Answer:
(b) B.K = \(\frac { 1 }{ MPc }\)

Question 30.
Which of the following is included in secondary sectors ?
(a) Insurance
(b) banking
(c) Trade
(d) Investment
Answer:
(d) Investment

Question 31.
Net national income at Factor cost is called :
(a) National Income
(b) Gross Investment
(c) Domestic Income
(d) None of these
Answer:
(a) National Income

Question 32.
The market value of all final goods and services produced in an economy over a year is called :
(a) Gross National Product
(b) National Income
(c) Gross Domestic Product
(d) Net National Product
Answer:
(c) Gross Domestic Product

Question 33.
Which service is included in Tertiary Sector ?
(a) Mining
(b) Communication
(c) Construction
(d) Animal Husbandry
Answer:
(b) Communication

Question 34.
GNPMP = ?
(a) GNP_MP – Depreciation
(b) GNP_MP + Net Factor Income from abroad
(c) GNP + Subsidy
(d) None of the above
Answer:
(b) GNPMP + Net Factor Income from abroad

Question 35.
Which of the following is correct ?
(a) Disposable Income = Personal Income – Direct Taxes
(b) Disposable Income = Private Income – Direct Taxes
(c) Disposal Income = Personal Income – Indirect Taxes.
(d) Disposal Income = Private Income – Indirect Tases
Answer:
(a) Disposable Income = Personal Income – Direct Taxes

Question 36.
Which Objectives government attempts to obtain by Budget ?
(a) To Promote Economic Development
(b) Balanced Regional Development
(c) Redistribution of Income and Wealth
(d) All the above
Answer:
(d) All the above

Question 37.
Which of the following Budget is suitable for Developing Economy ?
(a) balanced Budget
(b) Surplus Budget
(c) Deficit Budget
(d) None of these
Answer:
(c) Deficit Budget

Question 38.
Foreign exchange is determined by :
(a) Government
(b) Bargaining
(c) World Bank
(d) Demand and supply forces
Answer:
(d) Demand and supply forces

Question 39.
“Budget is a preliminary approval Plan of Public revenue and expenditure”. Who said?
(a) Rane stourn
(b) Findlay Shirras
(c) Taylor
(d) Dalton
Answer:
(d) Dalton

Question 40.
“Money is what mobey does” who said it ?
(a) Hartley Withers
(b) Hawtrey
(c) Prof Thomas
(d) Keynes
Answer:
(a) Hartley Withers

Question 41.
The function of money is
(a) Medium of exchange
(b) Measure of value
(c) Store of value
(d) All of the above
Answer:
(d) All of the above

Question 42.
What is Central Bank of India ?
(a) Central Bank
(b) Commercial Bank
(c) Private Bank
(d) Co-operative Bank
Answer:
(b) Commercial Bank

Question 43.
Who regulates money supply ?
(a) Govt, of India
(b) Planning Commission
(c) Reserve Bank
(d) Commmercial Bank
Answer:
(b) Planning Commission

Question 44.
Who is the Banker’s of the Bank ?
(a) Reserve Bank of India
(b) State Bank of India
(c) Unit Trust of India
(d) None of the above
Answer:
(a) Reserve Bank of India

Question 45.
In which year Banking Ombudsman Scheme was announced ?
(a) 1990
(b) 1955
(c) 1977
(d) 1988
Answer:
(b) 1955

Question 46.
Which type of currency is issued by the central Bank ?
(a) Currency
(b) Credit Money
(c) Coins
(d) All the above
Answer:
(a) Currency

Question 47.
Which items are included in Balance of Payments?
(a) Visible items
(b) Invisible items
(c) Capital Transfer
(d) All the above
Answer:
(d) All the above

Question 48.
Balance ot Trade means
(a) Capital Transaction
(b) Import Export of goods
(c) Total Debit and Credit
(d) All of the above
Answer:
(b) Import Export of goods

Question 49.
The meaningt of Spot Market relates to foreign exchange is ?
(a) Current Transactions
(b) Transactions of mid-period
(c) Transactions of Long Term
(d) None of these
Answer:
(a) Current Transactions

Question 50.
The Hybrid systems of exchange rate related to
(a) Wider Bands
(b) Crawing peg
(c) Managed Floating
(d) All of them
Answer:
(d) All of them

Non-Objective Type Questions

Short Answer Type Questions

Question no. 1 to 25 are Short answer type questions. Answer any 15 them in 50 words. Each question carries 2 marks. (15 x 2 = 30)

Question 1.
What do you understand by Micro Economics ?
Answer:
Small units of an economy are included in micro economics e.g. one consumer, one producer, one firm, one industry etc. In other words, individual units are studied in micro economics.

According to K.E. Boulding, “Micro economics may be defind as that branch of analysis, which studies the economics behaviour of the individual unit, may be a person, a particular house-hold or a particular firm. It is a study of one particular unit rather than all the units combined together,”

Question 2.
Write two main components of Macro Economics ?
Answer:
The term Macro in English shas its origin in the Greek term Macros which means large. In the context of macro economics “large” means economy as a whole. Thus, macro economic is defined as that branch of economics which studies economic activies at the level of an economy as a whole.

According to M.S. Spencer, “Macro-economics is concerned with the economy as a whole or large segments of it. In Macroeconomics, attention is focused on such problems as the level of unemployment, the rate of inflation, the nation’s total output and other maters, of economy-wide significance.”

Question 3.
Distinguish between utility and total utility. Ans. Demand schedulers that schedule which, other things, remaining constant, expresses the relation between different quantities of the commodity demanded at different prices. The table relating to price and quantity demanded is called the demand schedule.
Demand schedule is of two types :

• Individual demand schedule
• Market demand schedule.

1. A more and more units of a commodity are consumed the marginal utility derived from each successive unit goes on diminishing. But the total utility increases up a limit.
2. Marginal utility of the first four units, being positive the total utility goes on increasing thus, as long as the marginal utility of the commodity remains positive, total utility goes on increasing.
3. Marginal utility of the sixth unit is negative (-2). As a result of it, total utility of six units of the commodity falls from 20 to to 1 units.
   Thus,
   1. When MU diminishes, TU tends to increase at a diminishing rate
   2. When MU is zero, Tu is maximum
   3. When MU is negative, TU starts diminishing.

Question 4.
What is indifference curve ?
Ans. Indifference curve explains the consumer’s behaviour related with the combination of two goods and this consumer’s behaviour is explained with the help of “Indifference schedule or Indifference set.” various combinations of two goods giving equal satisfactions to the consumer become the component of ‘Indifference schedule’, When indifference schedule is represented on a graph paper, we get indifference curve.

In the words of watson “An indifference schedule is the lists of combination of two commodities, the list being so arrange that a consumer is indifferent to the combinations preferring more of any other”.

Question 5.
What are the exceptions of law of Demand ?
Answer:
There are following to the Law of Demand.

1. Expected rise in future price
2. Prestigious Goods
3. Ignorance of consumer
4. Giffin’s Paradox,

Question 6.
Explain any two factors that affect price elasticity.
Answer:
Factors affecting elasticity of demand are discussed below.

1. Substitutes : When substitute of any goods is available, then deamnd elasticity of such goods is highly elastic because when price of these goods increases, subsutities are used in place of it. In the same way on decrease in price of these goods, use of substitutes decrease. Tea, coffee, gas, sugar etc. are examples of subsitutes.
2. Alternative uses : When goods could be used in only one way, its demand will be elastsic and when it would be used in many ways, its demand will be elastic eg. coal has so many used-it can be used industries houses ralways etc. Demand of coal for railways in elastic but for house purpose, its cheeper alternative goods like wood cooking gas etc. could be used in place of it.

Question 7.
What do you understand by Production Function ?
Answer:
A Production expresses the technical relationship between input and output of a firm. It tells us about the maximum quantity of output that can be produced with any given quantities of inputs. If there are two factor inputs, labour (L) and capital (K), then production function can be written as :
Q = f (L, K) where
Q = Quantity of output
L = Units of labour
K = Units of capital
It may be pointed here that both the inputs are necessary for the production. If any of the inputs is zero, there will be no production with both inputs and output will also be zero, As we increase the amount of any one input, output increases.

Question 8.
What is difference between Explicit Cost and Implicit Cost ?
Answer:
Explicit cost: Explicit costs refer to the actual money outlay of the firm to buy or wire the productive resources, it needs in the process of proudction.
Implicit Costs : Implicit costs are payments which are not directly or actually paid out by the firm as no contractual disbursement is fixed for them. It includes the prices of such services and factors which are used in production process but are not directly paid.

Question 9.
Why does a firm attain maximum Profit When MR = MC ?
Answer:
MC stands for marginal cost incurred by a firm when its production raises by one unit. If the marginal cost is smaller than the marginal revenue (MR), then it is profitable for the firm to produce on extra Unit of output.

Question 10.
What are the different types of supply elastiicity ?
Answer:
Following are the types of elasticity supply.

1. Perfectly Elastic Supply (e_V = ∞)
2. Greater than unitary Elastic supply (e_s> 1)
3. Unitary Elastic Supply (e_s = 1)
4. Inelastic Supply (e_s < 1)
5. Perfectly Inelastic supply (e_s = 0)

Question 11.
Write three main features of monopoly market.
Answer:
Features of monopoly are as under-

1. One seller and large number of buyers : Under monopoly, there should be a single producer of a commodity. He may be alone or there may be a group of partner or a joint stock company. Thus, there is only one firm under monopoly. But the buyers of the product are in large number.
2. Restrictions on the entry of the new firms : Under monopoly, there are some estrictions on the entry of new firms into monopoly industry.
3. No close substitutes : A monopoly firm produces, a community that has close substitutes.
4. Full control over price : A monopolist has full control over its price. A monopolist thus, is a price maker. He can fix whatever price he wishes to fix for his product.
5. Possibility of price discrimination : A
   monopolist charges different prices from different consumers. It is called price descrimination. It refers to the practice by a seller of charging different prices from different buyers for the same good.

Question 12.
Explain the Circular Flow of Income.
Answer:
Production gives birth to income, income to consumption, consumption to ependiture and again expenditure to income and production. Thus, circular flow of income earning economic activities takes place in the economy.
According to hipster, “The circular flow of income is the flow of payment and receipt between domestic firms and domestic households.”

Hence, the circular flow of income refers to flow of money income or the flow of goods an services across different sectors of the economy in a circular form.

Question 13.
What are the uses of National Income Accounting ?
Answer:
The information collected through nation income accounting can be used for a variety of purposes, such as assessing the current standard of living or the distribution of income within a population. Additionally, national income accounting provides a method for comparing activities within different sectors in an economy, as well an changes within those sectors over time. A thorough anlysis can assist in determining overall economic stability within a nation.

Question 14.
What is the relationship between Gross Domestic Product and Gross national Product.
Answer:
Distinction between GDP and GNP :

Question 16.
What is the difference between Standard money and Token Money ?
Answer:
The Indian rupee is a mixture of the standard money and the token money. Like standard money. It is unlimited legal tender, and like the token money, its face value is greater than its intrinsic value.

Question 17.
State the qualiity of good money.
Answer:
Following are the qualities of good money :

1. Utility : The metal with which coin is made, must bear the feature of utility. The metal must easily be accepted. Gold and silver are such metals which possess utility.
2. Port ability : The metal with which coin is made, can easily be tranferred from one place to antother. Gold and silver coins bear this feature also.
3. Durable : Money is saved by people and hence coin should be made of such metal which is durable from saving purpose.
4. Divisibility : Money metal should be divisible without my loss in its value. Gold and silver are such metals having the feature of divisibility.
5. Homogeneity : All units, of money should be homogeneous.
6. Economy : Minting cost’of coin should be minimum and the depreciation in the coin should be least.
7. Stability of Value : Money metal should be stable in value i.e. price fluctuation in the metal of coin should be minimum.
8. Liquidity : Money metal should be liquid in nature, metal should easily be converted into coins can again be converted into meta on easily.
9. Cognisibility : Metal should easily be indentified. Take coins on easily be traced out if metal of money is cognisible. Gold and silver are such metals having full cognisibility.

Question 18.
What is difference between cash credit and overdraft ?
Answer:
At the simplest level, overdraft and cash credit are just forms of borrowing. The institution allows you to withdrew funds that you do not have, usually in small amounts. The primary differences between these forms of borrowing is how they are secured and whether the money is lent out of a separate account.

Question 19.
State the types of Government Budget.
Answer:
Following are the types of Budget.

1. Balanced Budget.
2. Deficit Budget.
3. Surplus Budget.

Question 20.
Mention any two participants of the Foreign Exchange Market.
Answer:
Following are the two participants of foreign exchange market.

1. Central Banks.
2. Foreign Exchange Brokers.

Question 21.
What is unfavorable Balance of Payment.
Answer:
Unequal flow of money under an unfavorable balance of payments will reduce the country’s money supply and increase the exchange rate to currencies in other countries, causing issues with inflation, unemployment and production. Also called balance of payments deficit.

Question 22.
Explain the relationship between investment Multiplier and Marginal Propensity to consume.
Answer:
The Multiplier Effect. The marginal propensity to consume (MPC) is equal to AC/AY, where AC is change in consumption, and AY is change in income. If consumption increases by eighty cents for each additional dollar of income, them MPC is equal to 0.8/1 = 0.8.

Question 23.
When does demand become Inelastic ?
Answer:
Demand becomes inelastic when people by about the same amount whether the price drops or rises. That happens with things people must have, like gasoline. Drivers must purchase the same amount even when the price increases. Like wise, they don’t buy much more even if the price drops.

Question 24.
Explain two features of oligopoly ?
Answer:
Important features of oligopalistic market are :

1. Few sellers
2. Interdependence among sellers regarding policies about price and output determination.

Question 25.
What is meant by Revenue Deficit ?
Answer:
Revenue deficit is the excess of revenue expenditure over revenue receipts. Revenue receipts include both tax revenue and non-tax revenue. Similarly revenue expenditures also include both plan and non-plan expenditures on revenue account. Revenue dificit does not include items of capital receipts and capital expenditure.
[Revenue Deficit] = [Revenue Expenditur] – [Revenue Receipts]

Long Answer Type Questions

Question no. 26 to 33 are Long answer type questions. Answer any 4 of them in 100 words. Each question carries 5 marks. (5×4 = 20)

Question 26.
Explain the law of Demand. What are its assumptions ?
Answer:
Law of demand-Low of demand explains quantitative relation behueen price of goods and quantity demanded. Every consumer has a psychology to buy less amount or quantity of anything of high price and more quantity of low price, ceteris Paribus (others being equal), there is inrerse relationship between price of a goods and when price is low, demand is high.

Thus, P ∞\(\frac { 1 }{ Q }\) where, P = Price of commodity, Q = Quantity demanded
Assumptions of the law of demand-Law of demand is based on few assumptions. These assumptions are-

1. Consumer’s income should remain contant.
2. Consumer’s taste, nature, etc. should remain constant
3. Price of related goods should remain constant
4. Consumer remains unknown with new substitutes
5. There is no possibility of price change in future.

Question 27.
Explain the factors determining elasticity of demand.
Answer:
Factors affecting Elasticity of Demand :

1. Substitutes : When substitutes of any goods is available, then demand elasticity of such goods is highly elastic, because when price of these goods increases, substitutes are used in pace of it. In the same way, on decrease in price of these goods, use of substitutes decreases. Tea, coffee, sugar, etc. are examples of substitutes.
2. Alternative Uses : When goods could be used in only one way, its demand will be inelastic and when it would be used in many ways, its demand will be elastic. For example, coal has many uses-it can be used in railways, houses, industries, etc. Demand of coal for railway is inelastic but for house purpose, its demand is elastic as many cheaper alternative goods like wood, cooking gas etc. could be used in place of it.
3. Postponement of Consumption : If consumption of any goods can be postponed, its demand becomes elastic, e.g., a person has to woolen clothes. If due to some reason, price of woolens clothes increases, then consumer postpones the idea of buying another sweater in current year. In such a case, demand of woolen clothes for current year will be highly elastic.
4. Expenditure Amount: Goods on which large part of income is spent, are highly demand elastic and those goods on which small part of income is spent, their demand is generally inelastic. That is why, demand of television, radio, cycle, scooter, etc. is more elastic as compared to salt, wheat etc.
5. Income Level : Elasticity of demand for rich people is generally inelastic because increase in price level does not affect them severly while elasticity of demand for poor people is highly elastic because increase in prices affect their purchasing power a lot.

Question 28.
Explain the law of variabie proportion.
Answer:
According to Mrs. Joan Robinson, s”The law of diminishing returns, as it is usually, formulated states that with a fixed amount of any one factor of production, successive increase in the amount of others will after a point, yield a diminishing increment of output.”
Assumptions of the Law :

1. One factor of production is variable and others are fixed
2. All units of variable factor are homogeneous
3. There is no change in level of technique
4. Fixed factors are indivisible
5. Different factors of production are imperfect substitutes
6. Fixed factors are limited and scarce.

Explaination of the Law or Three Stages of Production : Three stages of variable porportion have been depicted in the table :

Above table explains all the three stages of variable proportion :

(i) Stage of Increasing Returns : In the first stage, as the units of variable factor are increased with fixed factor, increased production takes place because as we increase units of variable factor, optimum utilisation of fixed factor becomes possible. Thereby, total production, average production and marginal production all increase in the beginning of stage of production.

There are two parts of the first stage. In the first part, MP and AP both increase. At third unit of variable factor, Mp is maximum. At fourth unit, MP decreases but AP continues to increase. In the beginning, both AP and MP increase but in second part of the stage, AP increases, although MP continues to decrease. The mid-point between first and second stage of production is called ‘Point of Inflexion’. First stage ends at the point where AP is maximum. In the first stage, AP in increasing continuously from starting till end. That is why, this stage is also called stage of
increasiong Average Return or Increasing Return Stage.

(ii) Stage of Diminishing Returns : In the second stage, AP and MP both are decreasing. This stage ends at the point, where MP becomes zero. In this stage, TP increases at a decreasing rate because MP is decreasing but remains positive.
In this stage, AP continues to decline and so, this stage is also called ‘Stage of Decreasing Average Product’.

(iii) Stage of Negative Returns : In this third stage of production, MP becomes negative or less than zero. Due to negative Marginal Product. Total Product (i.e., TP) starts declining. Due to decreasing TP and negative MP, this stage is also called ‘Stage of Negative Returns’.
Diagrammatic Representation
Stage I : Till ON quantity of variable factor.
Stage II: In between NS quantity of variable factor.
Stage III : After OS quantity of variable factor.

In above fig. Law of Variable Proportion has been represented. Other factors being fixed, change in quantity of one factor results in three different stages of production.

First Stage : Stage of Increasing Returns : This stage has been shown till ON quantity of variable factor. At the end of this stage, MP and AP become equal to each other (see point Q). In this stage, AP increases continuously and MP is positive and greater than AP as a result of which TP increases at the increasing rate. Reasons for increasing returns to a factor is that with less amount of variable factor in the beginning, optimum utilisation of fixed factors does not become possible.

As more and more units of variable factor are employed, intensive use of fixed factors becomes possible and production increases. In this way, additional units of variable factor increases efficiency of fixed factors. Fixed factors being indivisible cannot be used in lesser amount from technical point of view. So, they cannot be used with less amount of variable factor. Hence, more units of variable factor are used and it increases production. This is called increasing retunrs. In this stage, TP curve is shown point O to point K. OK can be divided into two parts or the first stage can be divided into two parts :

(a) Point O to Point F : TP is increasing with increasing rate because MP is continuously increasing till point P. Form point O to point F, TP is convex to X-axis.

(b) Point F to Point K : Total production increases but at a decresing rate because MP decreases but is positive (see point P to point Q). TP curve between point F to point K is concave to X-axis.

Point F on Total Product curve at which MP is maximum is called ‘Point of Inflexion’. After this point, total product increases at a decreasing rate.

Second Stage : Stage of Decreasing Returns : This stage has been shown on TP curve between point K and point T. In this stage, although TP increase but at a decreasing rate because both MP and AP i.e., marginal product and average product decreases. This stage, ends at the point, where MP is zero (Point S).

When MP is zero, then TP is maximum (see point T). This stage explains that if OS uits of variable factors are used, TP will be maximum. Reasons for decreasing returns an this stage are that fixed factors of production cannot be increased in short-run. When ON units of variable factors are.used with fixed factors, then MP decreases till zero level due to over utilisation of fixed fators and as a result of which internal diseconomies occur. In other words, extensive use of variable factors with fixed factors results in decline or decrease in MP.

Third Stage : Stage of Negative Returns : In this stage, Total Production (TP) starts decreasing after point T because at point T, marginal productivity of variable factors is zero. If after point S, an additional unit or marginal unit of variable factor is used, then marginal productivity of that additional unit becames negative and as a result TP starts declining. Therefore, this stage is called ‘Stage of Negative Returns’. In this stage, variable factors exceed fixed factors. This disbalanced or unequal ratio between the two, makes marginal productivity or variable factors negative.

Question 29.
Discuss the short-run cost curve with the help of diagram.
Answer:
Conceptually, in the short run, the quality of at least one input is fixed and the quantities of the other inputs can be varied. In tb. short-run period, factors, such as land and machi.iury, remain the same.

On the other hand factor such as labour and capital, vary with time. In the short run, the expansion is done by living more labour and in creasing capital. Following are the cost concepts that are taken into consideration in the short-run.

I. Total Fixed cost (T.F.C) : Refer to the cost that remain fixed in the short period. These costs do not change with the change in the level of output. Therefore, the slope of TFC curve is horizontal straight line.

II. Total variable cost (T.V.C) : Refers to the cost that change with the change in the level of production. If the output is zero, then variable cost is also zereo.

III. Total Cost (T.C.) : Involves the sum of TFC and TVC ss It can be calculated as follow total cost = TFC + TVC TC also changes with the changes in the level of output-on there is a change in TVC.

IV. Average Fixed Cost (AFC) : Refers to the per unit fixed costs of production. In other words, AFC inplies fixed cost of production divided by the quantity of output produced.
AFC = TFC/Output
TFC is constant on production increase, thus AFC falls.

V. Average Variable Cost (AVC) : Refer to the per unit variable cost of production. It implies organization’s variable costs divided by the quanity of output produced.
It is calculated as AVC = TVC/Outputty6

VI. Average Cost (AC) : Refers to the total costs- of production per unit of output.
AC is calculated as :
AC = TC/Output
AC = TC/Output
AC is equal to the sum of total of AFC and AVC

VII. Marginal Cost (MC): Refers to the addition to the total cost for producing on additional unit of product.
Marginal cost is calculated as :
MC = TC_N = TC_n-1
n = Number of units produced
It is calculated as :
MC = ATC/A Output

Question 30.
What is Perfect Competition ? Explain the characteristics of Perfect Competition.
Answer:
Perfect competition is that market situation in which a large number of buyers and sellers and found for homogeneous product single buyer or the seller are not capable of affecting the prevailing price and hence in a perfectly competition market, a single market price prevails for the commodity.
Features of Perfect Competition :

1. Large number of buyers and sellers : Perfect competition market has a large number of buyers and sellers and hence any buyer or seller can not influence the market price. In other words individual buyer or seller can not influence the demand and supply conditions of the market.
   Paper
2. Homogeneous product : The units sold in the market by all sellers are homogeneous (or identical) in nature.
3. Free entry and exit of firms : In perfet competition any new firm may join the industry or any old firm may quit the industry. Hence there is no restrication on free entry or exit of firms into/form the industry.
4. Perfect knowledge of the market: In perfect competition every buyer has the perfect knowledge of market conditions. None of the buyers will buy the commodity at higher price than the prevailing price in the market. Hence only one price prevails in the market.
5. Perfect mobility of factors : In perfect competition the factors of production are perfectly mobile. Factors can easily be mobile from one industry to other industry (or one firm to another firm) without any difficulty.
6. No transportation cost : Transportation cost remains zero in perfect competition due to which one price prevails in the market.

Question 31.
How the problems of double counting in computation of natonal income can be removed ?
Answer:
Meaning : Double counting means counting of the value of the same product (or ependiture) more than once. How ? According to output method, of calculating national income value of only final goods and services produced by all the production units of a country during a yera should be counted. In others words, value of intermediate goods which enter into final goods Ce.g. paper used in printing of books, raw cotton used in garments, wheat used in making breads, should not be taken into acount.

But in actual practice, while taking value of final goods, value of intermediate goods also gets included because every producer treats the commodity he sells as final irrespective of weather it is used as intermediate or final good. For instance, while taking value of final goods like cycles the value of tyres, tubes, frames, bells etc. (intermediate goods) used in manufacturing these cycles also gets included inadvertently.
In this way certain items are counted more than once resulting in over estimation of national product to the extent of the value of intermediate goods included. This is called the problem of double counting which means counting value of the same commodity more than once.

How to avoid Double Counting : Theoritically we may say that there may be two alternative ways of avoiding double counting namely
(i) final product approach
(ii) value added approach.
But in actual practice, double counting still occurs unintentionally- in final product approach because every producer treats the product he sells as final product though the same night have been used by the buyer as an intermediate product. Therefore, this problem is perfectly solved by value added method according to this method ‘instead of taking value of finai products, value added by eacb firm at each stage of production is included.

Clearly value added by all the four firms is Rs. 3500 comprising Rs. 1000 by A + Rs 500 by B + Rs. 700 by C + Rs: 1300 by D. There is no scope of double counting in this method. Thus to avoid double counting, the value added method also known as industry of origin method is used in computation of national income. It is worth mentioning that total value added is equal to value of final product.

Question 32.
What is Domestic Product ? How Gross Domestic Product is calculated ?
Answer:
Domestic product referss to the money value with in of all the final goods and services produced with in the domestic territory of a country, the following equation is used to calculate the Gross Domestic product (GDP): GDP = C +1 + G (X-M) or GDP = Private consumption + Gross isnvestment + government investment + government spending + (exports – imports).

It transforms the money value measure, nominal GDP, into an index for quantity of total output.

Question 33.
Explain main points of Keynesian theory of income and employment.
Answer:
According to Keynesian employment theory in short period; total production, i.e., national income in capitalist economy depends on the level of employment because in short period other factors of production such as capital, technique, etc., remain constant. Employment level depends on effective demand. That level of aggregate demand at which it becomes equal to aggregate supply is called effective demand.

Aggregate Demand : The total demand of goods and services in an economy is termed as ‘aggregate demands’ which is expressed in terms of total expenditure made in the economy. Thus, aggregate demand in an economy is measured in terms of total expenditure on goods and services.

In other words, aggregate demand refers to total expenditure that the residents of a country are ready to incur on the purchase of goods and services at given level of income.

Aggregate Demand = Consumption Expenditure + Investment Expenditure AD = C + I
Aggregate Supply : The concept of aggregate supply is related to the total supply of goods and services made available by all producers in the economy. It means that aggregate supply depends on the production made by producers.

A necessary condition of equilibrium (income level or employment level) in an economy is
Aggregate Demand = Aggregate Supply C+I=C+S

Classical viewpoint explains the income equilibrium level at full employment level, i.e., aggregate demand can equal aggregate supply only at a point of full employment.

Countrary to it, according to Keynesian viewpoint aggregate demand equals aggregate supply at the point before full employment level (i.e., taken place at underfull employment level). Aggregate demand has to be increased for increasing employment in the economy.

i.e. sin Keynesian viewpoint, under-full employment, equilibrium can be converted to full employment equilibrium only by increasing aggregate demand.

According to Keynes, “Under employment equilibrium is a situation in which aggregate demand (which is less than full employment aggregate demand) is equal to aggregate supply so that there is equilibrium but some resources remain unemployed.”

In this situation, factors are not fully employed and all laborers do not get employment. According to Keynes, under employment situation appears due to deficient aggregate demand but not due to deficiency of aggregate supply.
In above Fig. at ON 1 employment level, AD = AS but it is a situation of under-full employment. When aggregate demand AD increases to AD|, full employment level On is obtained.

Bihar Board 12th Biology Model Papers

Bihar Board 12th Biology Model Question Paper 2 in English Medium

Time : 3 Hours 15 Min
Total Marks : 70

Instructions for the candidates:

1. Candidates are required to give answers in their own words as far as practicable.
2. Figures in the right-hand margin indicate full marks.
3. While answering the questions, the candidate should adhere to the word limit as for as practicable.
4. 15 Minutes of extra time has been allotted for the candidates to read the questions carefully.
5. This question paper is divided into two sections: Section – A and Section – B
6. In Section – A, there are 35 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with blue/black ball pen against the correct option on OMR Sheet provided to you. Do not use Whitener/Liquid/ Blade/Nail on OMR Sheet otherwise result will be treated as invalid.
7. In Section – B, there are Non-objective type questions. There are 18 Short answer type questions, out of which any 10 questions are to be answered. Each question carries 2 marks. Apart from this, there are 6 long answer type questions, out of which any 3 of them are to be answered. Each question carries 5 marks
8. Use of any electronic device is prohibited.

Objective Type Questions

There are 1 to 35 objective type questions with 4 options. Choose the correct option which is to be answered on OMR Sheet. (35 x 1 = 35)

Question 1.
All tissue can be formed from
(a) Ectoderm
(b) Endoderm
(c) Mesoderm
(d) Stem cell
Answer:
(d) Stem cell

Question 2.
Astrogen and Progesterone are secreted by
(a) Ovary
(b) Testis
(c) Placenta
(d) All of the above
Answer:
(c) Placenta

Question 3.
Which one is not a part of anther wall?
(a) Endothecium
(b) Endothelium
(c) Tapetum
(d) All of the above
Answer:
(b) Endothelium

Question 4.
Which of the following is true fruit?
(a) Coconut
(b) Apple
(c) Pear
(d) Cashew
Answer:
(a) Coconut

Question 5.
Haploid chromosome number in dog is
(a) 23
(b) 39
(c) 19
(d) 4
Answer:
(b) 39

Question 6.
Which one does not show Oestrus cycle?
(a) Cow
(b) Sheep
(c) Monkey
(d) Dog
Answer:
(c) Monkey

Question 7.
Which one of the following is a major source of air pollution?
(a) Industries
(b) Automobiles
(c) Burning coals
(d) All of the above
Answer:
(d) All of the above

Question 8.
Bt cotton is resistant to
(a) Insects
(b) Weeds
(c) Salts
(d) None of the above
Answer:
(a) Insects

Question 9.
Lamarck was from
(a) India
(b) England
(c) France
(d) None of the above
Answer:
(c) France

Question 10.
Which among the following is a hereditary disease
(a) Haemophilia
(b) Diabetes
(c) Cretenism
(d) All of the above
Answer:
(a) Haemophilia

Question 11.
Which bacteria is helpful in the formation of curd from milk?
(a) Anabena
(b) Streptococcus
(c) Lactobacillus
(d) All of the above
Answer:
(c) Lactobacillus

Question 12.
The example of retrovirus is
(a) Plasmodium
(b) TMV
(c) HIV
(d) None of the above
Answer:
(c) HIV

Question 13.
Spermatogenesis produces
(a) Sperm
(b) Ova
(c) Zygote
(d) None of the above
Answer:
(a) Sperm

Question 14.
Humulin term is used for
(a) Digestive enzyme
(b) Antibiotic
(c) Chitin
(d) Human insulin
Answer:
(d) Human insulin

Question 15.
Pomato is a hybrid of
(a) Tomato and Cabbage
(b) Carrot and Radish
(c) Potato and Tomato
(d) None of the above
Answer:
(c) Potato and Tomato

Question 16.
The substance which causes a definite change in gene is called
(a) Mutagen
(b) Alkaloid
(c) Cytotoxin
(d) None of the above
Answer:
(a) Mutagen

Question 17.
Linkage was discovered by
(a) Muller
(b) Punnet
(c) Mendel
(d) Morgan
Answer:
(d) Morgan

Question 18.
A child with mother of A group and father of AB group will not have the following blood group
(a) A
(b) B
(c) AB
(d) O
Answer:
(d) O

Question 19.
The ratio 9 : 7 is produced due to
(a) Complementary genes
(b) Lethal genes
(c) Epistatic genes
(d) None of the above
Answer:
(a) Complementary genes

Question 20.
The exposure of X-ray enhances the frequency of
(a) Linkage
(b) Segregation
(c) Crossing over
(d) None of the above
Answer:
(c) Crossing over

Question 21.
Part of DNA which switch their position are called
(a) Exon
(b) Cistrons
(c) Transposons
(d) None of the above
Answer:
(c) Transposons

Question 22.
Nucleic Acids are polymers of
(a) Amino acid
(b) Nucleosides
(c) Nucleotides
(d) None of the above
Answer:
(c) Nucleotides

Question 23.
The lac operon consists of
(a) One structural gene
(b) Three structural gene
(c) Four structural gene
(d) None of the above
Answer:
(b) Three structural gene

Question 24.
The technique of DNA fingerprinting was initially developed by
(a) Alec Jeffreys
(b) Griffith
(c) Mirsky
(d) None of the above
Answer:
(a) Alec Jeffreys

Question 25.
In split genes, the coding sequences are called
(a) Exons
(b) Introns
(c) Cistrons
(d) Operons
Answer:
(a) Exons

Question 26.
Vermiform appendix is a
(a) connecting link
(b) vestigial organ
(c) homologous organ
(d) None of the above
Answer:
(b) vestigial organ

Question 27.
Use and disuse was proposed by
(a) Darwin
(b) Haeckel
(c) Lamarck
(d) None of the above
Answer:
(c) Lamarck

Question 28.
Modern man is called
(a) Neanderthals
(b) Ramapithecus
(c) Homosapiens
(d) None of the above
Answer:
(c) Homosapiens

Question 29.
Nervous system is influenced by
(a) Cocaine
(b) Heroine
(c) Hashish
(d) All of the above
Answer:
(d) All of the above

Question 30.
Pathogen of malaria is
(a) Aedes
(b) Wuchereria
(c) Anopheles
(d) Plasmodium
Answer:
(d) Plasmodium

Question 31.
The term ecology was coined by
(a) Odum
(b) Linnaeus
(c) Haeckel
(d) None of the above
Answer:
(c) Haeckel

Question 32.
Organisms which can inbreed with each other come under the same
(a) Kingdom
(b) Family
(c) Species
(d) Genus
Answer:
(c) Species

Question 33.
In a food chain, herbivores are
(a) Primary producers
(b) Primary consumers
(c) Secondary consumers
(d) None of the above
Answer:
(b) Primary consumers

Question 34.
Ovulation is induced by a hormone called
(a) FSH
(b) LH
(c) Both
(d) None of the above
Answer:
(b) LH

Question 35.
Bamboo species flower
(a) Only one in lifetime
(b) Every year
(c) Once in 12 years
(d) None of the above
Answer:
(c) Once in 12 years

Non-Objective Type Questions

Short Answer Type Questions

In this section, there are 18 short answer type question (each carryies 2 marks) out of which answers any ten (10) questions. (10 x 2 = 20)

Question 1.
Describe briefly a Technique of gel elecrophoresis.
Answer:
Gel electrophoresis is a technique of separating DNA fragments, formed by the action restriction endonucleases. The fragments of DNA are placed in typical agarose gel under an electric field. The DNA fragments move towards the anode as these fragments are negatively charged molecules. The DNA fragments separate (resolve) according to their size through sieving effect provided by the agarose gel. The smaller the fragments size, the farther it moves.

The separated DNA fragments are stained with ethidium bromide followed by exposure to UV radiation. The DNA fragments are seen as orange coloured and are cut out from the agarose gel and extracted from the gel piece. This step is known as elocution. The DNA fragments purified in this way are used in construction recombinant of DNA by joining them with cloning vectors.

Question 2.
Where is Bee-keeping practiced ? What are the main points for successful bee-keeping ?
Answer:
The bee-keeping is practised in area where there are sufficient bee pastures of wild shrubs, fruit orchards and cultivated crops. Bee-hives can be kept in one’s courtyard, on the verandah of the house or even on the roof.
The main points for successful bee-keeping are :

1. Selection of suitable location for keeping bees.
2. Knowledge of the nature and habits of bees.
3. Catching and hiving of swarms.
4. Management of bee-hives during different seasons.
5. Handing and collection of honey and bees wax.

Question 3.
Write a short note on Haemophilia.
Answer:
It is sex linked recessive disease which is transmitted from unaffected carrier female to male progeny. In this disease a single protein is affected that is a part of the cascade of proteins involved in the clotting of blood. As a result of this a simple cut results into non stop bleeding. The heterozygous female (carrier) for haemophilia may transmit the disease to sons. The possibility of a female to become haemophilic is extremely rare because mother of such a female has to one atleast carrier and the father should be haemophilic. The family pedigree of Queen Victoria has a number of haemophilic descendents as she was a carrier of the disease.

Question 4.
Name one organ analogous to the wings of bird. Why are they both analogous ? Can you include the wing of bat also with them under the same category ? Give reasons.
Answer:
The wings of an insect are analogous to the wings of bird. They are analogous because both perform the same function but have the dissimilar structure and origin. The wings of an insect are modified outgrowth of the body without having bone where-as wings of birds are modified fore-limbs. The wings of a Vt cannot be put under the same category. The wings of a bat and birds are homologous organs as both are modified and perform the same function of flying.

Question 5.
How does sickle cell anaemia is caused ? What are its symptoms?
Answer:
Sickle cell anaemia is caused by the substitution of valine for glutamine at the sixth position in |3 chain of globin molecule of haemoglobin. The mutant haemoglobin molecule undergoes polymerization under low oxygen tension causing the change in the shape of the RBC from biconcave disc to elongated sickle like structure. In this disease, red blood cells become elongated sickle like structure. It is autosomal disease due to recessive genes.

Symptoms-In this disease, red blood cells become elongated and curved under low oxygen tension. Individuals with this disease suffer attacks due to aggregation of red blood cells. These erythrocytes are destroyed more rapidly than the normal red blood cells leading to anaemia.

Question 6.
Define the term Biotechnology. Why has it become important lately?
Answer:
Biotechnology : It is the branch of micro-biological science which is concerned with the utilization of micro-organisms, plants and animal cells and their components to generate useful products and services in industrial processes.

Biotechnology has become very important because it gives us wide variety of products in immense qualities. Most of the industries for preparing alcohol, enzyme, antibiotic and vaccines etc. at large scale are using microbes. Through these products earlier used to prepare at home in meager amounts but biotechnology thas opened a new way with greater potentialities.

Question 7.
What is Adaptation? What type of adaptation is found in organisms of water?
Answer:
Adaptation is an attribute of the organism (morphological, physiological, behavioural) that enables the organisms to survive and reproduce in its habitat. Many adaptations have evolved over a long evolutionary time and are genetically fixed. In the absence of an external source of water, the Kangaroo rat in North American deserts is capable of meeting all its water requirement through the internal fat oxidation. It also has the ability to concentrate it urine so that minimum volume of water is used to remove excretory products.

Many desert plants have a thick cuticle on their leaf surfaces and have their stomata arranged in deep pits to minimise water loss through transpiration. Mammals from colder climates generally have shorter ears and limbs to minimise heat loss. This is called Allen’s Rule.

Question 8.
Explain main steps in plant breeding.
Answer:
Plant breeding as a technology has helped to increase yields to a very large extent. It is the purposeful manipulation of plant species in order to create desired plant types that are better suited for cultivation, give better yields and are disease resistant. Classical plant breeding involves crossing or hybridisation of pure lines, followed by artificial selection to produce plants with desirable traits of higher yield, nutrition and resistance to diseases. With advancements in genetics, molecular biology and tissue culture, plant breeding is now increasingly being carried out by using molecular genetic tools. Plant breeding programmes are carried out in a systematic way worldwide in government institutions and commercial companies.

Question 9.
Describe three advantages and three disadvantages of cross pollination in plants.
Answer:
Following are the three advantages of cross-pollination in plants:

• New hybrids of plants can be produced by this method.
• It introduces variations due to genetic recombination.
• The offsprings produce are better adapted to change in environment.

Three Disadvantages of Cross-pollination:

• There is enormous loss of pollen grains.
• Good characters can be diluted and undesirable characters will enter in the progeny.
• There is always a chance factor for it.

Question 10.
Distinguish between structural gene, regulatory gene and operator gene.
Answer:
Structural gene: This is a gene which has the information to code for amino acid sequence. It produces m-RNA to synthesize a specific polypeptide (enzymes) and it is regulated as a unit,by a single switch (operator).

Regulatory gene: It is a gene that produces repressor to inhibit the action of an operator gene and thus, turns off the operon. It also controls the rate of synthesis of the produces of other gene.

Operator gene: It is a gene which switches on or off the adjacent structural genes. When this gene is on, then the expression of structural genes occur to initiate the transcription and translation but in the off condition, no synthesis of polypeptide chain takes place.

Question 11.
Write a short note on ‘Adaptive Immunity’?
Answer:
Every antigen is processed by antigen-presenting cells like macrophages, B lymphocytes etc. The processed antigen is presented on the surface of these cells. A subgroup of T cells, called T-help cells, specifically interacts with the presented antigen and becomes activated. The activated T help cells then activate B cells and a sub-group of T cells called T cytotoxic cells in a specific manner. The activated B and T cytotoxic cells proliferate to produce clones. All the cells of a clone recognise the same antigen and eliminate it.

Question 12.
What is Biogas? Name the biomass and bacteria involved in the production of Biogas.
Answer:
Biogas is the mixture of gases (predominantly methane) produced during decay of biomass in the absence of oxygen. The biomass used in the production of biogas is animal dung, sewage, crop residues, vegetable wastes, water hyacinth, poultry droppings and wastes from agro-based industries. Methanogens (Methanobacterium) which grow anaerobically on cellulosic material produce large amount of methane along with CO₂ and H₂.

Question 13.
Expand ELISA. On what principle ELISA test is based?
Answer:
ELISA: means Enzymes Linked ImmunoSorbent Assay. This is a simple and versatile technique which is used most widely for the screening HIV and is based on the principle of Ag- Ab reaction.

Question 14.
How is rabies caused ? Write about its symptoms and control measures in brief.
Answer:
Rabies is caused by Iyssavirus type-1 which RNA containing virus. In man it is caused by the bite of a rabid dog. The disease is transmitted from one organism to other through the saliva which enters wound made by the bite of the animal.
Symptom: The virus stimulates nervous system and damage the cells of spinal cord and brain.
It causes high fever, severe pain. The victim develops fear from water (Hydrophobia)
Control:

• The patient should be isolated in a quiet room protected from external stimuli.
• A series of injections are advised to be injected.

Question 15.
What is Gene gun ? Give its utility.
Answer:
Gene gun: It is the new technology where vectorless direct gene transfer occurs in organisms. DNA coated into microscopic pellets is directly shot into target cells.

Utility: This technique is used to insert genes that promote tissue repair into cells near wounds, leading to a reduction of healing time.

Question 16.
Write the important symptoms of Down’s Syndrome.
Answer:
Down syndrome is also known as Trisomy. It is a genetic disorder caused by the presence of all or part of a third copy of chromosome -21 symptom.

• Developmental delays and physical and mental disabilities caused by genetic disorder.
• Flat face and short neck is present in child.

Question 17.
Write short notes on Global Warming.
Answer:
Global Warming is the phenomenon of increase in the global mean temperature caused by greenhouse gases. Due to global warming, there is average increase in temperature in the atmosphere.

Question 18.
What is transcription?
Answer:
The first step of protein syntheris is known as Transcription. During transcription step the instruction encoded in the DNA of the genes are transcribed into the nucleotide sequence code of a RNA. Because this RNA molecule causes the Protein Synthesis instruction in the word a ‘message’ from the gene to the ribosome. So, it is called mRNA.

Long Answer Type Questions

There are 6 long answers type question (each carrying 05 marks) out of which answers any three questions. (5 x 3 = 15)

Question 19.
Give an account of Anemophily.
Answer:
Anemophily is a mode of pollination or transfer of pollen grains from anther to stigma through the agency of wind. The flowers which are wind pollinated are called anemophilous. The anemophilous flowers are characterized by the following adaptations
(a) Flowers are small, colourless, inconspicuous, odourless and nectarless.
(b) Calyx and corolla are either reduced or absent.
(c) Filament of stamens are usually long and versatile.
(d) Pollen grains are small, light, dry, dusty and some times winged (e.g. pine).
(e) Pollen grains are infinite in number.
(f) Stigmas are hairy and branched.
(g) When flowers are unisexual, male flowers are more abundant than female flowers.
In bisexual flowers the stamens are generally numerous.
Examples of wind pollinated flowers are grasses, sugarcane, bamboo, maize etc.

Question 20.
Give an account of Recombinant DNA technology.
Answer:
rDNA technology:

1. DNA sequence is obtained from tissue culture.
2. Specific restriction endonuclease is selected from the specific bacteria.
3. Restriction endonuclease cuts specific DNA at the two ends.
4. Some restriction endonuclease cuts a matching DNA sequence from a plasmid.
5. Ligase enzyme which acts as a molecular glue joins the restriction fragment in the place vacated by the cut DNA segment of the plasmid. The plasmid DNA now contains foreign DNA and its DNA is called recombinant DNA (r.DNA)
6. Recombinant plasmids containing recombinant DNA are now injected into a host cell.
   This is done by electroporation.
7. Host bacterium divides to give multiple copies of recombinant DNA.
   

Question 21.
Define the following terms and give one example for each:
(a) Commensalism
(b) Parasitism
(c) Camouflage
(d) Mutualism
(e) Interspecific competition.
Answer:
(a) Commensalism: It is the type of interaction between two organisms where one is benefitted and the other is neither benefitted nor harmed.
Example: The sucker fish bears a sucker on the dorsal side of its head which helps it to attach itself to the body of the shark. It benefits the sucker fish to get free transportation as well as free food left behind by the Shark.

(b) Parasitism: It is a type of interaction between two organisms where one lives at the expense of other.
Here, one is benefitted (parasite) and the other is harmed (host).
Examples: Lice are parasite on humans and ticks on dogs.

(c) Camouflage: It is a type of protective mechanism in many animals where they assume different shapes and colours resembling to the background for deceiving the predators as well as for ensuring better survival.
Example: Stick insect (Carausins morosus) resemble like a dry stick and leaf insect (Phyllium) looks like a leaf. Similarly, Praying maints mimics the green foliage to protect themselves from the predators and prey.

(d) Mutualism: It is the relationship between two organisms where both are benefitted for food, shelter and substratum for attachment.
Example: The fungal symbiotic association with algae is called lichens. The algae manufacture the food and shares with fungi. On the other hand the fungus provides the structural converging the anchorage to the algae.

(e) Interspecific competition: It is the competition between the individuals of two different species occurring in a habitat. In shallow South American lakes, the visiting flamingoes and resident fishes have interspecific competition for their common food.

Question 22.
What are the various sources of water pollution? Name some important constituents of effluents.
Answer:
The water gets polluted by the following sources:
(a) Domestic Waste: The large quantities of municipal and household wastes are discharged into the water and cause water pollution.

(b) Industrial Wastes: The contamination of water occurs with the industrial wastes such as pulp mills, leather, tanneries, sugar and oil refinery, steel, textile and jute mills, petroleum and chemical fertilizer plants. These wastes contain very harmful substances like pesticides, bleaching powder etc. which largely affect the flora and fauna.

(c) Sewage: Disposal of sewage into rivers and lakes cause several undesirable effects. The sewage water contains several organic substances, human and animal excreta, food residues, cleaning agents, detergents and other wastes which provide nutrition to bacteria and fungi and consequently cause deoxygenation of water with the formation of algae blooms.

(d) Thermal Pollution: Release of large volumes of hot water into a stream can cause serious thermal pollution. This thermal pollution can upset the life-cycle and metabolic activities of many aquatic plants and fishes. Not only fish, but entire aquatic ecosystem is also affected by the thermal pollution and its toxic effect increases with further rise in temperature.

(e) Oils, Grease and Petroleum Products: These when discharged into water by accident or by design are extremely toxic and immediately affect the living organisms of the oceans.

(f) Radio Active Wastes: These wastes from atomic reactors and plants into rivers or streams can affect the aquatic plants and animals to a very great extent. They cause ionizations.

(g) Industrial Effluents: The increased quantity of dissolved salts in water like fluorine, alkalis, phenols, cyanides, mercury compounds, various metals, insecticides, pesticides and excess of fertilizers may produce harmful effect on living organisms. The consumption of mercury leads to crippling deformity called minamata disease.

Question 23.
What is pollution? Write an essay on air pollution.
Answer:
Pollution is an undesirable change in the physical, or biological characteristics of air, water and soil that may affect human life or any other organism. The World Health Organization defines air pollution as the presence of materials in the air in such concentration which are harmful to man and his environment. A number of ingradients find these are mostly gases, which rapidly spread over wide areas.

Sources of air pollution: The sources of air pollutions are very large and varied. These are:

(i) Industrial pollutants: The common air pollutants which are discharged by the industrial chimneys and power houses are S02, C02, H2S and hydrocarbon together with dust, smoke and girt.

(ii) Automobile exhausts: Automobiles run by petro and diesel produce carbon monoxide, nitrogen oxide and hydro-carbons. Hundred and thousands of tonnes of hydrocarbons and CO are emitted into air daily.

(iii) Ionizing radiations from radioactive substances: Ionizing radiations include ex, (3 particles and the gamma rays etc. These are produced by the atomic explosions and the testing of atomic weapons.

Air pollutants: The air pollutants have been separated into two categories directly from some identifiable sources.
These include: Sulphur compounds are SO₇, SO₃, H₂S etc.
Carbon compounds include oxides of carbon (CO + CO₂) and hydrocarbons.
Nitrogen compounds are NO₂ and NH₃
Halogen compounds are hydrogen fluoride (HF) and HC₁.

(ii) Secondary pollutants: The secondary pollutants are produced by the combination of primary emitted pollutants in the atmosphere.

Effects of Pollutants on Animals and Man: Only some of the direct or indirect effects of airborne pollutants on animal life have been studied so far. The general effect of air pollutants is on the respiratory tract and lung causing pulmonary Oedema and lung cancer. In addition to irritation in eyes, mucous membrane and pulmonary congestion, chronic bronchitis, lung carcinoma and other effects.

Flourosis in cattle is caused if exposed to fluoride-containing dusts. More subtle physiological effects of ciliary action, alternation in pulmonary physiology, specific enzyme inhibition and changes in blood chemistry. Inhaling of ozone causes dryness of membrane of mouth, nose and throat changes, visual activity causes headache, pulmonary congestion and oedema. Radio-active elements which enter the air through nuclear explosions come by earth as nuclear follents. These enter the biological system the absorption through the leaves or roots of plants and often result in the formation of cancer.

Control of Air pollution: Air pollution is caused mostly by human agencies. The use of cheap fuels with higher sulphur contents should be avoided. Use of expensive fuels of high quality should be recommended. Strict check on car exhaust should be maintained for contents. The poisonous gases going out in the atmosphere should be treated chemically. The persons working in chemical factories, polishing and spray industries should be provided with suitable gas dust masks.

Question 24.
What is radiation pollution? What are the effects of it?
Answer:
When in atmosphere harmful changes happen due to different types of radiations and radio-active materials then it is called radiation pollution. It is the physical pollution of air, water and soil with radioactive materials. It is natural as well as man-made. The effect of radioactive pollutants depends on (i) strength of radiation, (ii) rate of diffusion and deposition of the pollutants, (iii) the length of time for which the tissue is exposed to radiation, and (iv) half-life of pollutants. Environmental factors also influence their effects.

Effects of radiation pollution :

1. Due to radiation pollution, body becomes weak and life becomes short.
2. Radiation pollution is harmful for DNA, RNA, Protein, Spleen, etc.
3. Radio-active radiations cause sterility, defect vision, tumour of lungs, loss of tissues, etc.
4. Long time exposure in ultraviolet radiations causes skin related diseases.
5. For long time or time-to-time radiation of radio active materials may cause blood cancer or Leuckaemia.
6. Cells vary in their sensitivity to injury by radiation.
7. Chances of depletion of ozone layer in stratosphere by nuclear explosions.

Bihar Board 12th Chemistry Model Papers

Bihar Board 12th Chemistry Model Question Paper 1 in English Medium

Time : 3 Hours 15 Min
Full Marks: 70

Instructions for the candidates

1. Candidates are required to give answers in their own words as far as practicable.
2. Figures in the right hand margin indicates full marks.
3. While answering the questions, candidate should adhere to the words limit as far as practicable.
4. 15 Minutes of extra time has been allotted for the candidates to read the questions carefully.
5. This question paper is divided into two sections : Section -A and Section-B
6. In Section A, there are 35 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with blue/black ball pen against the correct option on OMR Sheet provided to you. Do not use Whitener/Liquid/Blade/ Nail on OMR Sheet otherwise your result will be treated as invalid.
7. In section-B, there are 18 short answer type questions (each carrying 2 marks), out of which only 10 (ten) questions are to be answered Apart from this there are 06 Long Answer type questions (each carrying 5 marks), out of which 3 questions are to be answered.
8. Use of any electronic device is prohibited.

Objective Type Questions

In the following questions no. from 1 to 35, there is only one correct answer against each question. For each question, mark (darken) the correct answer on the OMR Sheet provided to you. (1 x 35 = 35)

Question 1.
How many types of Crystals are found ?
(a) 2
(b) 6
(c) 4
(d) 3
Answer:
(c) 4

Question 2.
Which of the following bond is found in H₂O (ice)?
(a) Hydorgen bond
(b) Metallic bond
(c) Ionic bond
(d) All
Answer:
(a) Hydorgen bond

Question 3.
One Faraday of electricity is equal to how many coulombs ?
(a) 96500
(b) 96550
(c) 94500
(d) 96000
Answer:
(a) 96500

Question 4.
Inverse of resistance is called ………..
(a) Conductance
(b) Resistance
(c) Good conductor
(d) None
Answer:
(d) None

Question 5.
For strong electrolytes λm ………..
(a) increases on dilution
(b) decreases on dilution
(c) remains constant on dilution
(d) All
Answer:
(a) increases on dilution

Question 6.
Chemisorption is ………..
(a) Irreversible in nature
(b) Reversible in nature
(c) Arises due to Van-der-Waals forces
(d) Depends on nature of the gas
Answer:
(a) Irreversible in nature

Question 7.
Chief ore of Iron is ……..
(a) Magnetite (Fe₃O₄)
(b) Haematite (Fe₂O₃)
(c) Siderite (FeCO₃)
(d) Iron pyrite (FeS₄)
Answer:
(b) Haematite (Fe₂O₃)

Question 8.
Which type of ore can be concentrated by Electromagnetic separation method
(a) Non-magnetic particles
(b) Magnetic particles
(c) Sulphide ores
(d) All the above options
Answer:
(b) Magnetic particles

Question 9.
Copper matte contains :
(a) Cu₂S and Cu₂O
(b) Cu₂S and FeS
(c) CuS₂ and Fe₂O₃
(d) Cu₂S and Cu
Answer:
(b) Cu₂S and FeS

Question 10.
Group 15 of Periodic Table includes Nitrogen and …………..
(a) Oxygen
(b) Phosphorous
(c) Carbon
(d) Argon
Answer:
(b) Phosphorous

Question 11.
d-block elements are also known as …………….
(a) Transition elements
(b) Typical elements
(c) Non-transition elements
(d) Alkali metals
Answer:
(a) Transition elements

Question 12.
d-block elements are also known as ………….
(a) Transition elements
(b) Typical elements
(c) Non-transition elements
(d) Alkali metals
Answer:
(a) Transition elements

Question 13.
Zinc is a ………..
(a) Transition element
(b) Lanthanide
(c) Normal element
(d) Element of s-block
Answer:
(c) Normal element

Question 14.
Mn³⁺ is an oxidising agent because………..
(a) half filled K₂-level
(b) Completely filled e_g level
(c) empty d-orbital
(d) All of the above
Answer:
(a) half filled K₂-level

Question 15.
U.P.A.C name of K₂[Zn(OH)₄] is………..
(a) Potassium tetrahydroxoxincate (II)
(b) Zinc di-hydroxide
(c) Zinc hydroxide potassium
(d) None
Answer:
(d) Racemic mixture

Question 16.
The stereo isomens related to each other as non- super imposable mirror images are called
(a) diastereomers
(b) enantiomers
(c) chiral compound
(d) Racemic mixture
Answer:
(a) diastereomers

Question 17.
Chloroform on treatement with O₂ in presence of light gives ………..
(a) Phosphene
(b) Phosgene
(c) Phosphorescence
(d) Methane
Answer:
(b) Phosgene

Question 18.
Alcohols and Phenols are formed when one of the hydrogen atom of Alkane and Arenes are replaced by which group ?
(a) – Cl
(b) – OH
(c) – CHO
(d) – COOH
Answer:
(b) – OH

Question 19.
Glycerol is a …………..
(a) Monohydric alcohol
(b) Di-hydric alcohol
(c) Trihydric alcohol
(d) Tetrahydric alcohol
Answer:
(c) Trihydric alcohol

Question 20.
Simplest hydroxy derivative of Benzene is ………….
(a) Propanol
(b) Phenol
(c) Benzylal cohol
(d) None
Answer:
(b) Phenol

Question 21.
IUPAC name of the compound

(a) 2, 5-dimethyl Phenol
(b) l-Hydroxy-2-methyl toluene
(c) 1-Hydroxy-2, 3-dimethyl benzene
(d) Hydroxy dimethyl benzene
Answer:
(a) 2, 5-dimethyl Phenol

Question 22.
Chloro-ethane on reacting with ammonia gives …………
(a) Ethanamine
(b) Propanamine
(c) Benzylamine
(d) Ethane nitrile
Answer:
(a) Ethanamine

Question 23.
Amides on reduction with LiAlH₄ ………………
(a) Alkanes
(b) Alkylamines
(c) Alcohols
(d) Acids
Answer:
(b) Alkylamines

Question 24.
IUPAC name of HCOOH is …………..
(a) Ethanoic acid
(b) Formic acid
(c) Methanoic acid
(d) Oxalic acid
Answer:
(c) Methanoic acid

Question 25.
IUPAC name of Oxalic acid is …………..
(a) Metanoic acid
(b) Ethanoic acid
(c) Ethanedioic acid
(d) Benzene
Answer:
(c) Ethanedioic acid

Question 26.
The formula of Methylnitrile is ……………
(a) CH₃NC
(b) CH₃CN
(c) C₂H₅CN
(d) C₂H₅NC
Answer:
(b) CH₃CN

Question 27.
Simple Carboxylic acid are soluble in water due to formation of………………………….
(a) Co-Valent bond
(b) Hydrogen bond
(c) Ionic.hood
(d) None
Answer:
(a) Co-Valent bond

Question 28.
The formula of Fructose is ……………
(a) C₆H₁₂O₆
(b) C₁₂H₂₂O₁₁
(c) C₆H₁₂O₅
(d) C₆hH₆O₆
Answer:
(b) C₁₂H₂₂O₁₁

Question 29.
Carbohydrate that yields three to ten mono­saccharides units on hydrolysis are called ………..
(a) Mono-saccharide
(b) Oligo-saccharide
(c) Poly-saccharide
(d) Di-saccharide
Answer:
(a) Mono-saccharide

Question 30.
Amino acid contains two functional groups, one is – COOH and other is …………
(a) – OH
(b) – NH₃
(c) – NH₂
(d) NH₄
Answer:
(b) – NH₃

Question 31.
Polymers of a-amino acid is called …………….
(a) Protein
(b) Peptines
(c) Peptides
(d) Dipeptides
Answer:
(b) Peptines

Question 32.
Polythene is a polymer of ?
(a) Ethane
(b) Ethene
(c) Ethyne
(d) Propene
Answer:
(b) Ethene

Question 33.
Rubber, Starch, Cellulose and Protein are ……………
(a) Synthetic polymers
(b) Natural Polymers
(c) Semi-Synthetic polymers
(d) None of the above
Answer:
(b) Natural Polymers

Question 34.
Buna- N and Buna- S are the types of ……………….
(a) Natural rubber
(b) Synthetic rubber
(c) Polythene
(d) Bakelite
Answer:
(b) Synthetic rubber

Question 35.
The drug used to reduce fever is known as ………………..
(a) Antacid
(b) Analgesic
(c) Anti-pyretic
(d) Anti-biotic
Answer:
(c) Anti-pyretic

Non-Objective Type Questions

Short Answer Type Questions

In this Section, there are 18 Short answer type questions (each carrying 2 marks), out of which answer any 10 questions.

Question 1.
What do you mean by Frenkel’s Defect ?
Answer:
This defect is shown by those ionic solids in which there is a large difference in the size of ions,
e.g. ZnS, AgCl, AgBr, Agl.

Question 2.
What do you mean by an Ideal solution ?
Answer:
Ideal solutions obc, Rault’s law over entire range of concentration. For these solution A_mix H = O and A_mix V = O.
In binary solutions, if A – B interactions are nearly equal to A – A or B – B interactions then it is an ideal solution. Solutions of n -hexane & n-heptane, bromoethane & chloroethane, benzene & toluene, etc., are nearly ideal in behaviour.

Question 3.
Define Osmotic pressure ?
Answer:
The hydrostatic pressure which develops on account of osmosis is called Osmotic pressure or the excess pressure that must be applied on the solution to prevent osmosis is called Osmotic pressure.
Osmotic pressure (π) is directly proportional to molarity (C) of the solution at a given temperature π α C
\(\pi=\mathrm{CRT} \text { or, } \pi=\frac{n_{2}}{\mathrm{V}} \mathrm{RT}\left[\text { where }, \mathrm{C}=\frac{n_{2}}{\mathrm{V}}\right]\)

Question 4.
Why Copper sulphate is not stored in zinc pot ?
Answer:
Zinc is stronger reducing agent than copper. Thus zinc forms zinc sulphate during chemical reaction. Therefore, copper sulphate is not stored in zinc pot.
Zn + CuSO₄ → ZnSO₄ + Cu

Question 5.
In Nernst equation
\(\mathbf{E}=\mathbf{E}^{0}-\frac{\mathbf{R} \mathbf{T}}{\mathbf{n} \mathbf{F}} \mathbf{I n} \frac{[\mathbf{M}]}{\left[\mathbf{M}^{\mathbf{n}+}\right]} \mathbf{R}\)
Answer:
It gives the relation between electrode potential, temperature and concentration of metal Ions.

When T = 298 K, F = 96500 C mol-¹
R = 8.314 J K^-1 & concentration of solid M is taken as unity.

Question 6.
Define Cell Constant ?
Answer:
Cell constant : The quantity l/a is called cell constant where ‘l’ is the distance of two electrodes and ‘a’ is the area of cross section of electrode. It is expressed in the units cm^-1.
\(Cell constant =\frac{\text { Distance between the electodes }}{\text { Area of Cross }-\text { Section }}\)

Question 7.
What are Enzymes ?
Answer:
Enzymes are complex nitrogenous organic compounds. They are usually protein molecules of high molecular mass. These are biochemical catalysts as numerous reactions that occur in the bodies of animals & plants to maintain the life process are catalysed by enzymes.

Question 8.
Why does PH₃ fumes in moist air ?
Answer:
PH₃ reacts with moist air to form impure phosphine, which bums in air and forms dense white smoke of metaphosphoric acid.

Question 9.
Why H₂O is liquid and H₂S is gas at room temperature ?
Answer:
H₂O contains hydrogen bonding but H₂S does not contain hydrogen bonding due to oxygen is more electro­negative than sulphur.

Question 10.
On what ground you will say that, Scandium (Z = 21) is a transition metal ?
Answer:
The last electron of Scandium enters in 7-orbital. It has vacant 7-orbital.
Sc (Z = 21)-Is² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹, due to vacant 7-orbital & entering of last electron scandium is a transition element.

Question 11.
Which Ore is stronger reducing agent Cr²⁺ or Fe²⁺ ? Explain.
Answer:
Cr²⁺ is a stronger reducing agent than Fe²⁺.
This is quite evident form the E° values. E° Cr³⁺/Cr²⁺ = – 0.4/V and E° Fe³⁺/Fe²⁺ = 0.77 V.
Reason : T⁴ → 7³ occurs when Cr²⁺ changes to Cr³⁺ ion while T⁶-) T⁵ takes place when Fe²⁺ gets converted to Fe³⁺ ion. Now d⁴ → 7³ transition is easier as compared to T⁶ → T³ transition. Therefore, Cr²⁺ is a stronger reducing agent than Fe²⁺.

Question 12.
What do you mean by inner-transition elements ?
Answer:
The last electron added to each element is an f- electron. These two series of elements are hence called the inner transition elements (f-block Elements). The two rows of elements at the bottom of the Periodic Table, called the Lanthanoids, Ce (Z = 58) – Lu (Z = 71) & Actinoids, Th (Z = 90) – Lr (Z = 103).

Question 13.
What do you mean by co-ordination number ?
Answer:
Co-ordination number : The number of co­ordinate covalent & covalent bonds formed by the central metal of a complex compound is called co-ordination number of the central metal.
Example : [Ag (NH₃)₂]C1 C.N of Ag⁺ ion is 2.

Question 14.
Define Bidentate Ligand ?
Answer:
Bidentate or didentate Ligands: Ligands which has two donar atoms and has tendency to attach to the central ion through two donar atoms. Examples are

Question 15.
What Aldehyde on oxidation will give ?
Answer:
On oxidation aldehyde gives carboxylic acid

Question 16.
Name one water soluble and one fat soluble Vitamin.
Answer:
(a) Water soluble vitamins – (Vitamin B & C)
(b) Fat-soluble vitamins-(Vitamin A, D, E & K)

Question 17.
Define Molarity and Mole fraction.
Answer:
Molarity (M) : It is defined as the number of moles of solute dissolved in one litre (or one cubic decimetre) of the solution.
\(\text { Molarity }(\mathrm{M})=\frac{\text { Number of moles of solute } \times 1000}{\text { Volume of solution }(\mathrm{m} l)}\)
Molality (m) : It is defined as the number of moles of solute per kilogram of the solvent.
\(\text { Molality }(\mathrm{m})=\frac{\text { Number of mol. of solute } \times 1000}{\text { Mass of solvent }(\mathrm{g})}\)

Question 18.
Differentiate between Condensation and Polymerisation.
Answer:
Condensation : The condensation polymers are formed by repeated condensation reaction between two monomeric units having different bifunctional and trifunctional groups with the elimination of small molecules like water, alcohol, hydrogen chloride etc.
Example : Nylon 6, 6

Polymerisation: The process of formation of polymers from respective monomers is called polymerisation,

Long Answer Type Questions

There are 06 long answer type questions (each carrying 05 marks), out of which answer any there questions.
(5 x 3 = 15)

Question 19.
Find the order of reaction of the following :
(a) Rate = K[A]^1/2 [B]^3/2
(b) Rate = K[A]^3/2 [B]^-1
Answer:
(a) Rate = K[A]^1/2 [B]^3/2
Therefore order = \(\frac{1}{2}+\frac{3}{2}=\frac{4}{2}=2\)
This is called second order reaction.

(b) Rate = K [A]^3/2 [B]^-1
Therefore, order = \(\frac{3}{2}+(-1)=\frac{3}{2}-1=\frac{3-2}{2}=\frac{1}{2}\)
This is first order of reaction

Question 20.
Write in brief about how Sulphuric acid is manufactured by Contact process ?
Answer.
Sulphuric Acid (H₂SO₄) : It is called the king of chemicals and is one of the most widely used industrial chemicals. Manufacture : Sulphuric acid is manufactured by contact process which involves 3 steps

• Burning of sulphur or sulphide ores in air to produce SO₂
  
• Conversion of SO₂ into SO₃ by reaction with air in the presence of catalyst U₂O_s.
• Absorption of SO₃ in H₂SO₄ to give Oleum (H₂ S₂ O₇)

The key step is the catalytical oxidation of SO₂ with O₂ to give SO₃ in the presence of V₂O₅.

The SO₃ gas is absorbed in concentrate H₂SO₄ to produce Oleum (H₂S₂O₇) which on dilution with water gives H₂SO₄ of desired concentration.
SO₃ + H₂SO₄ → H₂ S₂ O₇ (Oleum)
H₂S₂O₇+ H₂O → 2H₂SO₄ The sulphuric acid obtained by the contact process is 96 – 98% pure.

Question 21.
What happens when.
(i) Concentrated H₂S0₄ is added ict Calcium fluoride and heated ?
(ii) SO₃ is passed through water.
Answer.
(i) When concentrated H₂SO₄ is added to calcium fluoride and heated it gives calcium sulphate (CaSO₄) and hydrogen fluoride (HF)
CaF₂ + H₂SO₄ → CaSO₄ + 2HF

(ii) When SO₃ is passed through water it gives sulphuric acid.
SO₃ + H₂O → H₂SO₄

Question 22.
Write the electronic configuration of the following :
(a) Cr³⁺ (b) Cu⁺ (c) CO²⁺ (d) Fe²⁺ (e)Mn²⁺ [Atomic number of Cr = 24, Cu = 29, Co = 27, Fe = Mn = 25]
Answer.
(a) Cr³⁺ – [Ar] 3d³ 4s°
(b) Cu⁺ – [Ar] 3d¹⁰ 4s°
(c) Co²⁺ – [Ar] 3d⁷ 4s°
(d) Fe²⁺ – [Ar] 3d⁶ 4s°
(e) Mn²⁺ – [Ar] 3d⁵ 4s°

Question 23.
How will you convert the following ?
(a) Methane to Ethane
(b) Ethanol to Ethyl acetate
(c) Metane to Chloroform
(d) Ethanal to Ethanoic acid
(e) Acetic acid to methane
Answer.
(a) Methane to Ethane

(b) Ethanol to Ethyl acetate

(c) Metane to Chloroform

(d) Ethanal to Ethanoic acid

(e) Acetic acid to methane

Question 24.
Write short notes on
(a) Inductive effect
(b) Resonance
Answer.
Inductive effect: It is the process of displacement of electrons along, the chain of carbon atoms due to the presence of a polar covalent bond at one end of the chain. This is a permanent effect.
(a) – I effect: When the atoms or group of atoms of the polar covalent bond is more electro-negative than C, it is said to show -I effect.

(b) + I effect: If the substituent attached to the end of the carbon chain is electron donating, the effect is called + I effect.

Resonance : Molecules having two or more structures due to distribution of electrons but same molecular formula is called resonance.
e.g.Benzene molecule has the following structure.

It is represented by a double headed arrow (<->) between the resonating structure.

Conditions :

• The nuclei in each of the canonical structures must be in the same relative position.
• The resonating structure differ only in the way of distribution of electrons.

Bihar Board 12th Physics Model Question Paper 1 in English Medium

Bihar Board 12th Physics Model Papers

Instructions for the candidates :

1. Candidates are required to give answers in their own words as far as practicable.
2. Figures in the Right-hand margin indicates full marks.
3. While answering the questions, candidates should adhere to the words limit as far as practicable.
4. 15 Minutes of extra time has been allotted to read the questions carefully.
5. This question paper is divided into two sections : Section -A and Section-B
6. In Section A there are 35 Objective type questions which are compulsory, each carrying 1 mark. Darken the circle with Blue/Black ball pen against the correct option on OMR Sheet provided to you. Do not use Whitener/Liquid/ Blade/Nail on OMR Sheet, otherwise, your result will be treated as invalid.
7. In section-B, there are 18 Short answer type questions (each carrying 2 marks), out of which only 10 (ten) questions are to be answered Apart from this there are 06 Long Answer type questions each carrying 5 marks, out of which 3 questions are to be answered.
8. Use of any electronic device is prohibited.

Time : 3 Hours 15 Minute
Total Marks : 70

Objective Type Questions

In the following questions from no. 1 to 35, there is only one correct answer against each question. For each question, mark (darken) the correct answer on the OMR Sheet provided to you. (1 x 35 = 35)

Question 1.
The force acting between two electrons separated by distance r is proportional to
(a) r (b) r² (c) r^-2 (d) r^-1
Answer:
(c) r^-2

Question 2.
The dimensional formula for electric flux is
(a) [ML² T^-3 l^-1] (b) [ML³ T^-3 l^-1] (c) [ML² T⁺³ l^-1] (d) [ML³ T^-3 l]
Answer:
(b) [ML³ T^-3 l^-1]

Question 3.
The Torque experienced by an electric dipole of electric dipole moment \(\overrightarrow{\mathrm{P}}\) in a uniform field \(\overrightarrow{\mathrm{E}}\) is

Answer:
\(\text { (a) } \overrightarrow{\mathrm{P}} \times \overrightarrow{\mathrm{E}}\)

Question 4.
The work done in moving a unit positive charge through a distance x on an equipotential surface is
(a) xj (b) \(\frac{1}{x} j\) (c) zero (d) x²j
Answer:
(c) zero

Question 5.
The electric field intensity inside a charged hollow spherical conductor is
\((a) \epsilon_{0}
(b) E o \sigma
(c) zero
(d) \frac{\epsilon \circ}{\sigma}\)
Answer:
(c) zero

Question 6.
A conductor of capacity 20 mF is charged to 1000 V. The potential energy of the conductor will be
(a) 20 x 10⁴ J (b) 10⁴ J (c) 20 x 10³ J (d) 10³ J
Answer:
(d) 10³ J

Question 7.
The emf of a cell is measured by
(a) Voltmeter (b) Potentiometer (c) Ammeter (d) Voltameter
Answer:
(b) Potentiometer

Question 8.
Kirchoff’s current rule is related to Principle of conservation of
(a) Momentum (b) Energy (c) Charge (d) Angular momentum
Answer:
(c) Charge

Question 9.
Electron volt (eV) is a measure of
(a) Potential difference (b) Charge (c) Energy (d) Current
Answer:
(c) Energy

Question 10.
The Torque experienced by current carrying loop of magnetic moment \(\overrightarrow{\mathbf{M}}\) placed in a magnetic field \(\overrightarrow{\mathbf{B}}\) is

Answer:
(a)

Question 11.
Resistance of Galvanometer is G. Shunt used to allow 1 % of main current through the Galvanometer is
\((a) \frac{\mathrm{G}}{99}
(b) \frac{\mathrm{G}}{90}
(c) \frac{\mathrm{G}}{100}
(d) \frac{99 \mathrm{G}}{100}\)
Answer:
\(\text { (a) } \frac{\mathrm{G}}{99}\)

Question 12.
A Current is flowing in a circular coil. If the radius of the coil is doubled, then the value of magnetic field intensity at its centre will be
(a) same (b) half (c) double (d) four times
Answer:
(b) half

Question 13.
The working of a Dynamo is based on
(a) heating effect of current (b) electro-magnetic induction (c) induced magnetism (d) induced electricity
Answer:
(b) electro-magnetic induction

Question 14.
Unit of self inductance is
(a) Weber (Wb) (b) Ohm (Ω) (c) Henry (d) Gauss
Answer:
(c) Henry

Question 15.
If N₁ and N₂ are number of turns in primary and secondary coil of a transformer, then
(a) N₁ > N₂ (b) N₂ > N₁ (c) N₁ = N₂ (d) N₁ = 0
Answer:
(b) N₂ > N₁

Question 16.
Power factor of L – R circuit is

Answer:
(b)

Question 17.
The ratio of value of magnetic field at same distance from mid point of a small magnet at its axial and equatorial position is
(a) 2′: 1 \(\text { (b) } 1: \sqrt{2}\) \(\text { (c) } \sqrt{2}: 1\) (d) 1 : 2
Answer:
(a) 2 : 1

Question 18.
The angle of dip at magnetic pole of earth is
(a) 0° (b) 90° (c) 45° (d) 180°
Answer:
(b) 90°

Question 19.
The direction of transmission of the electromagnetic wave is
(a) parallel to \(\overrightarrow{\mathrm{E}}\) (b) parallel to \(\overrightarrow{\mathrm{B}}\) (c) parallel to \(\overrightarrow{\mathrm{B}} \times \overrightarrow{\mathrm{E}}\) (d) parallel to \(\overrightarrow{\mathrm{E}} \times \overrightarrow{\mathrm{B}}\)
Answer:
(d) parallel to \(\overrightarrow{\mathrm{E}} \times \overrightarrow{\mathrm{B}}\)

Question 20.
An air bubble inside water shines due to
(a) refraction (b) reflection (c) total internal reflection (d) diffraction
Answer:
(c) total internal reflection

Question 21.
The equivalent focal length of co-axial contact combination of two lenses of power -15D and +5D will be
(a) -10 cm (b) +10cm (c) -20 cm (d) +20 cm
Answer:
(a) -10 cm

Question 22.
The final image in astronomical telescope is
(a) Real and inverted (b) Virtual and erect (c) Virtual and inverted (d) Real and erect
Answer:
(b) Virtual and erect

Question 23.
Cylindrical lenses are used to correct defect of eye is called
(a) Myopia (b) Hypermetropia (c) Astigmatism (d) Presbyopia
Answer:
(c) Astigmatism

Question 24.
In Rayleigh scattering of light, the intensity of scattered light is proportional to the wave-length X in the form of
\((a) \frac{1}{\lambda^{2}}
(b) \frac{1}{\lambda}
(c) \frac{1}{\lambda^{3}}
(d) \frac{1}{\lambda^{4}}\)
Answer:
\((d) \frac{1}{\lambda^{4}}\)

Question 25.
The colour of a thin film is due to
(a) interference (b) diffråction (c) scattering (d) dispersion
Answer:
(a) interference

Question 26.
Ilrcwstcrs Jaw is
(a) μ = cos i_p
(c) μ = sin i_p
(b) μ = tan i_p
(d) μ = cot i_p
Answer:
(a) μ = cos i_p

Question 27.
The energy of a photon of wave-length λ is
(a) \(\frac{h c}{\lambda}\) (b) \(\frac{h \lambda}{C}\) (c) hcλ (d) \(\frac{\lambda}{\mathrm{hc}}\)
Answer:
(b) \(\frac{h \lambda}{C}\)

Question 28.
Which of the spectral line of hydrogen spectrum lies in visible region?
(a) 50 Hz (b) 25 Hz (c) 100 Hz (d) 200 Hz
Answer:
(a) 50 Hz

Question 29.
Which one of the following is a chargeless particle?
(a) α-partcle (b) β-partcle (c) proton (d) photon
Answer:
(a) α-partcle

Question 30.
The time during which the quantity of any radio¬active material becomes half of its original value is called
(a) Average age (b) Half age (c) Decay constant (d) Time period
Answer:
(b) Half age

Question 31.
The majority charge carrier in /i-type semi¬conductor is
(a) a-partcle (b) electron (c) proton (d) hole
Answer:
(b) electron

Question 32.
In full wave rectification, if input frequency is 50 Hz, then output frequency will be
(a) 50 Hz (b) 25 Hz (c) 100 Hz (d) 200 Hz .
Answer:
(a) 50 Hz

Question 33.
The Boolean – expression for NAND gate is
\(\text { (a) } \overline{A+B}=Y\) (b) A + B = Y \(\text { (c) } \overline{A.B}=Y\) (d) A.B = Y
Answer:
\(\text { (c) } \overline{A.B}=Y\)

Question 34.
Result of conversion of decimal number 15 into Binary will be
(a) (1100)₂ (b) (1001)₂ (c) (1111)₂ (d) (11001)₂
Answer:
(c) (1111)₂

Question 35.
Which frequency range is used in TV transmission?
(a) 30 Hz – 300 Hz (b) 30 KHz – 300 KHz (c) 30 MHz – 300 MHz (d) 30 GHZ – 300 GHz
Answer:
(c) 30 MHz – 300 MHz

Section – II

Non-Objective Type Questions
Short Answer Type Questions

Question nos. from 1 to 18 are short answer type questions. Each question of this category carries 2 marks. Answer any ten (10) questions.

Question 1.
What is Electrostatic Shielding? Give its practical application.
Answer:
Electrostatic Shielding:
The electrostatic shielding is the best way to protect some area in vacuum or in alir from the influence of externd electric field.

The technique of electrostatic shielding is applied basically in designing the cable of television.

Question 2.
Give two factors which affect capacitance of a capacitor.
Answer:
The capacity of a capacitor depends upon the following two factors.
(a) On the surface area of the plate of the capacitor.
(b) Distance between the two plates of the capacitor.

Question 3.
Define current density \(\overrightarrow{\mathrm{J}}\) and write expression for Current density in terms of Drift velocity.
Answer:
Current density The current per unit area of conductor is called Current density. It is denoted by J.
\(\mathrm{J}=\frac{1}{\mathrm{A}}\)

It is a Vector quantity.
S.I. unit Ampere/m²
We know that I = ηAeV_d; \(\mathrm{V}_{\mathrm{d}}=\frac{\mathrm{I}}{\eta \mathrm{Ae}} ; \quad \mathrm{V}_{\mathrm{d}}=\frac{1}{\mathrm{ne}}\)

Question 4.
A wire of 12 Ω resistance is stretched to double its length. Find out the new resistance of the wire.
Answer:
In this position volume remains constant

Question 5.
Explain Ampere’s circuital law.
Answer:
Ampere’s circuital law : It states that the line integral of magnetic field \(\overrightarrow{(B)}\) around any closed path or circuit is equal to μ₀ times of total current (I) threading the closed circuit.
\(\oint \overrightarrow{\mathrm{B}} \cdot \overrightarrow{\mathrm{d} 1}=\mu_{0} \mathrm{I}\)
where μ₀ = permeability of vacuum.

Question 6.
What is Shunt? Explain its uses.
Answer:
Shunt :
It is wire of low resistance, joined in parallel with circuit. The current capacity of pivoted type galvanometer is not very large. When large current passes through the cirucit then its coil may burn. To save them from damage, a low resistance wire is joined in parallel and it is called Shunt.

Uses of Shunt :

• In the protection of coil of Galvanometer
• In the conversion of Galvanometer into Ammeter.

Question 7.
Lenz’s law is the law of conservation of energy. Explain.
Answer:
Lenz’s Law : It states that the induced current produced in a circuit always flows in such a direction that it opposes the change or the cause that produces it.

According to Lenz’s law, the induced emf. opposes the change that produces it. It is this opposition against which we perform mechanical work in causing the change in magnetic flux. So, it is the mechanical energy which is converted into electrical energy. Thus, Lenz’s law is in accordance with the law of conservation of energy.

Question 8.
State two differences betwen the magnetic properties of soft iron and steel.
Answer:
Magnetic properties of steel and soft iron :
Steel have high value of retentivity and high value of coercivity. The area of hystersis loop is large for steel. So, it is used to make permanent magnet.

The soft iron have high retentivity and low coercivity. The area of hysteresis loop is small for soft iron, so it is used to make electro-magnet.

Question 9.
Explain Wattless current.
Answer:
Three properties of electro-magenetic waves :

• The electro-magnetic waves are produced by accelerated charges.
• Electro-magnetic waves do not require any material medium for their propagation.
• The electro-magnetic waves obey the principle of Superposition.

Question 10.
State two main characteristics of electro-magnetic waves.
Answer:

• Electromagnetic waves are emitted by electrically charged particles undergoing acceleration.
• Electromagnetic waves of different frequency are called by different names. Since they have different source and effects no matter.

Question 11.
Two thin convex lenses of power 4D and 6D are placed co-axially at a distance of 20 cm apart. Find the focal length and power of the combination of lenses.
Answer:

Question 12.
Write necessary conditions for Interference?
Answer:
Necessary conditions for Interference of light.

• The two sources should emit the light waves continuously.
• The light waves should be of same wave-length.
• The light waves emitted should preferably be of the same amplitude.
• The two light sources should be very narrow.
• The two sources of light must be very close to each other.

Question13.
Write Truth table and Boolean algebraic expression of OR gate and AND gate.
Answer:
Boolean expressiosn of OR gate A + B = Y
Truth table for OR gate

Boolean expression for AND gate A • B = Y Truth table for AND gate

Question 14.
Write the de-Broglie wave-length of an electron of Kinetic energy E.
Answer:
de-Broglie wave length of an electron :
Let m is mass of electron, e is the charge and it is accelerated with potential v.
Energy of electron E = ev …………………….. (i)

K.E. of electron

where h = Plank” constants.

Question 15.
What is Amplitude Modulation? Explain.
Answer:
Amplitude Modulation When the modulating wave is superimposed on a high-frequency carrier wave in a manner that the frequency of the modulated wave is same as that of the carrier wave but its amplitude is modified in accordance with that of the modulating wave the process is called amplitude modulation.

Question 16.
What will be the value of flux of electric field on a closed surface ABC placed near charges +q₁ +q₂ and -q₃?

Answer:
Total charge inside the closed surface = + q₁ – q₃
total electric flux charge q₂ is outside Φ = \(\frac{q_{1}-q_{3}}{\epsilon_{0}}\) the closed surface.

Question 17.
In going from water to glass will speed of light increase or decrease? Explain.
Answer:
When the light ray passes from water to glass its speed decreases because glass is denser medium in comparision to water. When light ray passes from water to glass its wave length decreases. So, speed of light also decreases.

Question 18.
A particle of mass m and charge q is projected with velocity \(\overrightarrow{\mathrm{v}}\) perpendicular to a uniform magnetic field \(\overrightarrow{\mathrm{B}}\). The particle is set in a circular motion. What will be the radius of this circular path?
Answer:
When the charge particle moves perpendicular to magnetic field then its experiences the force F = qBVsinθ
Here θ = 90°; F = qBV ……………………..(i)
when it moves on aircular path then centripetal force
\(F=\frac{m V^{2}}{r}\) …………… (ii)

From equation (i) and (ii)
\(\frac{m v^{2}}{r}=q B V ; m v=q B r ; \quad r=\frac{m v}{q B}\)
This is the expression for radius of circular path.

Long Answer Type Questions

Question nos. from 19 to 24 are long answer type questions. Each question of this category carries 5 marks. Answer any three questions. (3 x 5 = 15)

Question 19.
State Gauss’s law. Applying this law obtain electric field due to an infinitely long thin uniform charged straight wire.
Answer:
Gauss’s Theorem :
It states that the total electric flux through a closed surface enclosing a charge is equal \(\frac{1}{\epsilon_{0}}\) to times the magnitude of charge enclosed.
\(\phi=\frac{q}{\epsilon_{0}}\)

where ε₀ = permitivity of vacuum or air Expression for electric intensity due to infinitely long charged st. wire.

Consider a thin infinitely long st. line charge having a linear charge density λ placed along yy’.

To find electric field due to line charged at point P distance r from it, draw a cylindrical surface of radius r and length l about the line charge as its axis. The cylindrical surface may be treated as the Gaussian surface for the line charge.

If E is the magnitude of electric field at point P, then electric flux through the Gausssian surface is given by
Φ = E x Area of curved surface of cylinder
Φ = E x 2πrl …………………… (i)

According to Gauss’s theorem

Question 20.
Establish the formula for a lens
\(\frac{1}{f}=(\mu-1)\left(\frac{1}{\mathbf{R}_{1}}-\frac{1}{\mathbf{R}_{2}}\right)\)
Answer:
Lens Maker’s Formula :
Suppose L is a thin lens. The refractive index of the material of lens is n₂ and it is placed in a medium of refractive index nx. The optical centre or lens is C and X. X is principal axis. The radii of curvature of the surfaces of the lens are Rj and R₂ and their poles are P₁ and P₂. The thickness of lens is t, which is very small. O is a point object on the principal axis of the lens. The distance of O from pole P₁ is u. The first refracting surface forms the image of O at V at a distance v’ from P₁. From the refraction formula at spherical

The image I acts as a virtual object for second surface and after refraction at second surface, the final image is formed at I. The distance of I from pole P₂ of second surface is v. The distance of virtual object (E) from pole P₂ is (v -1).

For refraction at second surface, the ray is going from second medium (refractive index n₁) to first medium (refractive index (n₂), therefore from refraction formula at spherical surface.
\(\frac{n_{1}}{v}-\frac{n_{2}}{\left(v^{\prime}-1\right)}=\frac{n_{1}-n_{2}}{\mathrm{R}_{2}}\) …………………….. (ii)

For a thin lens t is negligible as compared to v’, therefore from (ii)

where \(\mathrm{l} n_{2}=\frac{n_{2}}{n_{1}}\) is refractive index of second medium (i.e., medium of lens) with respect to first medium.

If the object O is at infinity, the image will be formed at second focus i.e.,

if u = ∞, v = f₂ = f , Therefore from equation (iv)

This is the formula of refraction for a thin lens. This is also called Len’s maker’s formula.

Question 21.
Define Interference of light. Derive an expression for Fringe-Width in Young’s double slits experiment.
Answer:
Interference of Light :
The phenomenon of non-uniform distribution of energy in the medium due to superposition of two light waves is called interference of light.

Expression for Fringe Width :
Consider that two coherent source of light S₁ and S₂ are placed at a distance apart and screen is placed at a distance D from the plane of two source. Let P be a point on the screen at distance y from the centre of screen. If .v is the path difference between light waves reaching point P from the source S₁ and S₂ then x = S₂P – S₁P

Fringe Width :
The spacing between any two consecutive fright fringes is equal to the width of dark frine therefore width of dark fringe.

Thus, in Young’s double slit experiment, the bright and dark fringes are of same width. It is denoted by β.
\(\beta=\frac{D \lambda}{d}\)

Question 22.
State KirchofTs laws. Applying these laws obtain the condition for balanced Wheatstone Bridge.
Answer:
Kirchoff’s law : First law :
In the network of conductor the algebraic sum of current meeting at a point is always zero. It also causes junction rule.

Second law :
It states that in any closed part of an electrical circuit, the algebraic sum of the emf is equal to the algebraic sum of the products of the resistance and current flowing through them. It is also called loop rule. This law is based on the law of conservation of energy.

Wheatstone bridge :
It is one of the accurate arrangements for measuring an unknown resistance. It is based on the principle of Kirchoff s law.

Four resistances P, Q, R and S are connected to form a quadrilateral of galvanometer and a tapping key k₁ (called galvanometer) are connected between points B and D as shown in the figure.

Applying Kirchoff s second law, for closed part ABDA in the circuit I₁ P + I_g g – (I – I₁) S = 0
where g is the resistance of galvanometer In the balanced state I_g = 0

Applying Kirchoff s law in closed part BDCB

From equation (i) and (ii)
\(\frac{P}{S}=\frac{Q}{R}\left[S=\frac{P}{Q} \cdot R\right]\)

Thus unknown resistance can be calculated.

Question 23.
State Biot-Savart law. Applying this law obtain expression of magnetic Held at a point on the axis of a circular coil carrying electric current.
Answer:
Biot-Savart law :
This law establish the relation between magnetic field and current.

Let xy is aonductor in which current I is flowing from v to y. P is the point at the distance r and at this point magnetic field \(\overrightarrow{d B}\) depends upon following factor :

where μ₀ is permeability of vacuum or air.

Magnetic field at the axis of a circular loop :
Consider a circular loop of radius R carrying current I, with its plane perpendicular to the plane of paper. Let P be a point of observation on the axis of this circular loop at a distance x from its centre O. Consider a small element of length dl of the coil at point A. The magnitude of the magnetic induction \(\overrightarrow{\mathrm{dB}}\) at point P due to this element is given by

The direction of \(\overrightarrow{\mathrm{dB}}\) is perpendicular to the plane containing \(\overrightarrow{\mathrm{dl}}\) and \(\overrightarrow{\mathrm{r}}\) is given by Right hand screw rule. As the angle between I \(\overrightarrow{\mathrm{dl}}\) and \(\overrightarrow{\mathrm{r}}\) is 90°, the magnitude of the magnetic induction \(\overrightarrow{\mathrm{dB}}\) is given by,
\(\overrightarrow{d B}=\frac{\mu_{0} I}{4 \pi} \frac{d l \sin 90^{\circ}}{r^{2}}=\frac{\mu_{0} I d l}{4 \pi r^{2}}\)

If we consider the magnetic induction produced by the whole of the circular coil, then by symmetry the components of magnetic induction perpendicular to the axis will be cancelled out, while those parallel to the axis will be added up. Thus the resultant magnetic induction \(\overrightarrow{\mathrm{B}}\) at axial point P is along the axis and may be evaluated as follows :

The component of \(\overrightarrow{\mathrm{dB}}\) along the axis,

Therefore the magnitude of resultant magnetic induction at axial point P due to the whole circular coil is given by

Question 24.
What is Zener diode? Explain its use in a Voltage regulator.
Answer:
Zener diode :
The specially designed Junction diode, which can operate in the reverse breakdown voltage region continuously without being damaged are called Zener diode.

Symbol of Zener diode

Zener diode as a voltage regulator :
The use of Zener diode is based on the fact that in reverse break down region, a very small change in voltage across the Zener diode produces a very large change in the current through the circuit.

If voltage is increased beyond Zener voltage, the resistance of the Zener diode drops considerably. Consider that the Zener diode and a resistance R, called dropping resistor are connected to fluctuating d.c. supply, such that the Zener diode is reverse biased. Whenever voltage across the diode tends to increase, the current through the diode rises out of proportion and causes a sufficient increase in voltage drop across the dropping resistor. As a result, the output voltage lowers back to the normal value. Similarly, when the voltage across the diode tends to decrease, the current through the diode goes down out of proportion, so that the voltage drop across the dropping resistor is much less and now the output voltage is raised to normal.

Bihar Board 12th Business Studies Model Papers

Bihar Board 12th Business Studies Model Question Paper 5 in English Medium

Time : 3 Hour 15 Min
Full Marks : 100

Instructions

1. Candidates are required to give their answers in their own words as far as practicable.
2. Figures in the right hand margin indicate full marks.
3. 15 minutes of extra time has been allotted for the candidate to read the questions carefull.
4. This question paper has two sections : Section -A and Section-B.
5. In Section-A, there are 50 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with black/blue ball pen against the correct option on OMR Sheet provided to you. Do not use Whitener/ Liquid/Blade/Nail on OMR Sheet, otherwise the result will be treated as invalid.
6. In Section-B, there are 25 Short answer type questions, out of which any 15 questions are to be answered. Each question carries 2 marks. Apart from this, there are 08 Long answer type questions, out-of which any 04 of them are to be answered. Each question carries 5 marks.
7. Use of any electronic device is prohibited.

Objective Type Questions

Question No. -1 to 50 have four options provided, out of which only one is correct. You have to mark, your selected option, on the OMR-Sheet. Each questiion carries 1 (one) mark. [50 x 1 = 50]

Question 1.
Profession in an Art _________
(a) Work by other
(b) Self work
(c) Both (a) and (b)
(d) None of these
Answer:
(a) Work by other

Question 2.
Project Evalution is _________
(a) 1986
(b) 1987
(c) 1968
(d) None of these
Answer:
(a) 1986

Question 3.
Risk capital establishment established For _________
(a) Import Analysis
(b) Export Analysis
(c) Both (a) and
(d) None of these
Answer:
(a) Import Analysis

Question 4.
A good Plane is ________
(a) Expensive
(b) time consuming
(c) flexible
(d) rigid
Answer:
(c) flexible

Question 5.
“Management is a profession.” This statement is of _________
(a) George R. Terry
(b) Henry Fayol
(c) American Management Association
(d) Lawrence A. Appley.
Answer:
(c) American Management Association

Question 6.
Of all managerial activities planning is the _________
(a) beginning
(b) end
(c) beginning & end both
(d) none of these
Answer:
(a) beginning

Question 7.
For delegation of authority to be effective, it is essential that accompanied with is necessary
(a) authority
(b) main power
(c) incentives
(d) Promotion
Answer:
(a) authority

Question 8.
Recruitment in the life of organisation is _________
(a) continuous
(b) occasionally
(c) once
(d) twice
Answer:
(a) continuous

Question 9.
In effective communication. language should not be used.
(a) expressive
(b) impressive
(c) ambiguous
(d) courteous
Answer:
(c) ambiguous

Question 10.
Who was the father of scientific management ?
(a) H. S. Parsons
(b) Diemer
(c) F. W. Taylor
(d) Charles Babbage
Answer:
(c) F. W. Taylor

Question 11.
Method (s) of training is /are _________
(a) conference
(b) lectures
(c) apprenticeship
(d) all of these
Answer:
(a) conference

Question 12.
Henry Fayol’s principles of management are _________
(a) 10
(b) 3
(c) 14
(d) 15.
Answer:
(c) 14

Question 13.
Financial manager takes decision as to _________
(a) finance
(b) investment
(c) dividend
(d) all of these
Answer:
(a) finance

Question 14.
Effective controlling is _________
(a) static
(b) pre-determined
(c) dynamic
(d) all of these
Answer:
(c) dynamic

Question 15.
Supervision is an element of _________
(a) leadership
(b) planning
(c) direction
(d) none of these
Answer:
(c) direction

Question 16.
Capital market deals in _________
(a) short-term funds
(b) medium-term funds
(c) long-term funds
(d) all of these
Answer:
(d) all of these

Question 17.
Consumer Protection Act was passed in _________
(a) 1886
(b) 1986
(c) 1996
(d) 1997
Answer:
(b) 1986

Question 18.
Headquarters of SEBI is in _________
(a) Delhi
(b) Mumbai
(c) Kolkata
(d) Chennai
Answer:
(b) Mumbai

Question 19.
Grapewine is _________
(a) formal Communication
(b) barriter to communication
(c) lateral communication
(d) Informal communication
Answer:
(a) formal Communication

Question 20.
Marketing includes _________
(a) Purchase
(b) Sales
(c) Warehousing
(d) All of these
Answer:
(d) All of these

Question 21.
Advertisement is deemed as _________
(a) Wastage
(b) Investment
(c) Luxury
(d) None of these
Answer:
(b) Investment

Question 22.
Bank overdraft facilities are available on _________
(a) Savings Bank Account
(b) Current Account
(c) Term Deposit Account
(d) None of these
Answer:
(b) Current Account

Question 23.
New issued shares deal in _________
(a) Secondary Market
(b) Primary Market
(c) Secondary Market and Primary Market both
(d) None of these
Answer:
(b) Primary Market

Question 24.
Budget is a statement of budgetary policy.
(a) Financial
(b) Final
(c) Work
(d) Non-financial
Answer:
(a) Financial

Question 25.
Main component (s) of New Economic Policy is/ are _________
(a) Liberalisation
(b) Globalisation
(c) Privatisation
(d) All of these
Answer:
(b) Globalisation

Question 26.
Authority cannot be delegated of _________
(a) Routine work
(b) Secret work
(c) Ordinary work
(d) None of these
Answer:
(b) Secret work

Question 27.
The proporinder of adminisimtive management was _________
(a) Fayol
(b) Taylor
(c) Terry
(d) None of these
Answer:
(b) Taylor

Question 28.
Which of the following depends on the sweet will of employees ?
(a) Formal Organisation
(b) Informal Organisation
(c) Functional Organisation
(d) Divisional Organisation
Answer:
(b) Informal Organisation

Question 29.
Co-ordination is _________
(a) voluntary
(b) necessary
(c) unnecssary
(d) waste of time
Answer:
(b) necessary

Question 30.
Fixed capital is needed for period _________
(a) short
(b) long
(c) short and long both
(d) none of these
Answer:
(b) long

Question 31.
Controlling is the aspect management.
(a) Theory
(b) Behaviour
(c) Mental
(d) Physical
Answer:
(b) Behaviour

Question 32.
Which of the following is not a characteristic of entrepreneurship ?
(a) Risk taking
(b) Innovation
(c) Creative activity
(d) Managerial training
Answer:
(d) Managerial training

Question 33.
Comprehensive plan for accomplishing an organisation’s objectives as _________
(a) Policy
(b) Programme
(c) Objective
(d) Strategy
Answer:
(d) Strategy

Question 34.
Barrier in effective communication is _________
(a) language
(b) distance
(c) individual differences
(d) all of these
Answer:
(c) individual differences

Question 35.
Which one amongst the following is not the Consumer product _________
(a) Raw material
(b) Refrigrator
(c) Old figure
(d) Share
Answer:
(c) Old figure

Question 36.
The disputes which come under Consumer Protection Act are _________
(a) disputes as to sale of shares by a company
(b) disputes of Penal Nature
(c) disputes as to sale of defective goods by the seller
(d) service disputes.
Answer:
(c) disputes as to sale of defective goods by the seller

Question 37.
Entrepreneurial Development institute of India is situated in _________
(a) Ahmedabad
(b) Mumbai
(c) New Delhi
(d) Chennai
Answer:
(a) Ahmedabad

Question 38.
The organisation spreading rumours is called _________
(a) Formal
(b) Informal
(c) Centralised
(d) Decentralised
Answer:
(b) Informal

Question 39.
The maximum duration of commercial paper is _________
(a) 3 months
(b) 6 months
(c) 12 months
(d) 24 months
Answer:
(a) 3 months

Question 40.
Stock exchange protects the interest of _________
(a) Investor
(b) Company
(c) Government
(d) None of these
Answer:
(a) Investor

Question 41.
which following is called “The Father of Scientific Management.”
(a) Alton Meyo
(b) F. W. Taylor
(c) Feyol
(d) None of these
Answer:
(b) F. W. Taylor

Question 42.
Management is :
(a) An art
(b) A science
(c) An art and science both
(d) None of these
Answer:
(c) An art and science both

Question 43.
14 principle of management is represented _________
(a) Henry Feyol
(b) F. W. Taylor
(c) Peter Drucker
(d) A. H. Maslo
Answer:
(a) Henry Feyol

Question 44.
In which following is important step in planning ?
(a) Decision
(b) Organiation
(c) Asiimption
(d) Direction
Answer:
(c) Asiimption

Question 45.
To whom social liabilities of management :
(a) To whole society
(b) Employee class
(c) Government
(d) Organisation
Answer:
(a) To whole society

Question 46.
What is the function of management ?
(a) Planning
(b) Organisation
(c) Direction
(d) None of these
Answer:
(d) None of these

Question 47.
The main object of budgeting is :
(a) Planning
(b) Co-ordination
(c) Controlling
(d) None of these
Answer:
(c) Controlling

Question 48.
“Scope of controlling” principle represented by :
(a) Henry Feyol
(b) Alton Meyo
(c) F. W. Taylor
(d) None of these
Answer:
(b) Alton Meyo

Question 49.
In inspiration’s “the principle of originated necessities” represented by :
(a) Hurjburg
(b) Maslo
(c) Alton Meyo
(d) None of these
Answer:
(b) Maslo

Question 50
communication is that _________
(a) One-sided process
(b) Two-sided process
(c) Multiple-sided process
(d) None of these
Answer:
(a) One-sided process

Non-Objective Type Questions

Short Answer Type Questions

Question no. 1 to 25 are Short answer type questions. Answer any 15 out of them. Each question carries 2 marks. (15 x 3 = 30)

Question 1.
State the nature and characteristics of Principles of Management.
Answer:
Management Principles : These are the statement of fundamental truth based on creation and systematic analysis which provides guidlines for managerial decision making and action.
Nature and charecteristics of management Principles are the same which are following :

1. Flexiblity
2. Univarsal application
3. lack of unanimity
4. Beharourial.

Question 2.
What do you mean by Scientific Management ?
Answer:
Meaning : Scientific management means a sound management technique that tends to eliminate wastage harmonises the different factors and processes of production and pings about an all around efficiency in the working of the organisation.

Definition : Scientific management means knowing exactly what you want men to do and seeing that they do it in the best and the cheapest way.

Question 3.
State the meaning of Liberalisation.
Answer:
Industrial economy in India has always been regulated by licensing system and bureaucratic procedure regulated in red – tapism and rampant corruption.These obstacles obstructed economic growth. Liberalization is the process of freeing the economy from licence system and other regulations.
Features of liberalisation :

1. Simplifying importance export procedure
2. Simplifying the process of attracting foreign capital and technology,
3. To do away with the necessity of having a license for most of the industries
4. Removing restrictions for the movement of goods and services from one place to another
5. Freedom in determining the scale of business activities
6. Freedom to fix, the prices of goods and, services
7. Reduction in the rate of taxes
8. Freedom from unnecessary control over economy.

Question 4.
Describe the limitations of planning.
Answer:
The major limitations of planning are as follows:

1. Planning leads to rigidity : A well defined plan is drawn up with specific goals to be achieved within a specific time frame.These plans then decide the future course of action and managers may not be in the position to change it.This kind of rigidity in plans may create difficulty.
2. Planning may not work in a dynamic environment : The business environment is dynamic, nothing is constant.Planning cannot foresee everything and thus, there may be obstacles to effective planning.
3. Planning reduces creativity : Planning is an activity which is done by the top management.Usually the rest of the members just implements these plans.Thus, planning in a way reduces creativity since people tend to think along the same lines as others.There is nothing new or innovative.
4. Planning involves huge costs : When plans are drawn up huge costs are involved in their formulation.These may be in terms of time and money for example,checking accuracy of facts may involve lot of time.
5. Planning is a time – consuming proces :
   Sometimes plans to be drawn up take so much of time that there is not much time left for their implementation.
6. Planning does not grantee success.

Question 5.
What is financial management ?
Answer:
Financial management is concerned with optimal procurement as well as usage of finance for optimal procurement, different available sources of finance are identified and compared in terms of their costs and associated risks. Similarly, the finance so procured needs to be invested in a manner that the returns from the investment exceed the cost at which procurement has taken place. Financial management aims at reducing the cost of funds procured keeping the risk under control and achieving effective deployment of such funds. It also aims at ensuring availability of enough funds whenever required as well as avoiding idle finance.

Question 6.
Explain the elements of directing function of management.
Answer:
Direction includes the following elements:

1. Supervision : The term ‘supervision’ is normally used in management to mean overseeing the employees at work. Itimplies, instructing, observing, monitoring and guiding the subordinates at work place to ensure that plans and procedures are implemented as intended.
2. Communication : Communication is a process which involves a sender of- massage and a receiver.Communication is complete only when the receiver is able to interpret the massage as desired by the sender and responds to it.Communication is regarded as a two way process.The process of communication begins when one person wants to transmit a fact; idea ,opinion or other information to someone else.
3. Leadership : Leadership may be defined as the process of influencing the behavior of people at work towards the realization of specified goals.lt involves ability to use non- conceive influence on the activities,goals and motivation of others for achieving organizational objectives.
4. Motivation : Motivation is a mental state. lt is a driving force that people to action and continuous them in action.Motivation is the set of forces that cause people to behave in certain ways.

Question 7.
What is function of Stock Marketing ?
Answer
The functions of stock markets are mentioned below :

1. Liquidity : Stock exchange provides a ready market for the securities issued by various institutions.
2. Promotes the habit of saving and investment: Stock exchange promotes the habit of saving and investment among the general public.
3. Safety of Dealing : Stock exchange protects the interests of investors against malpractices or dishonesty through

(a) strict enforcement of rules and regulations, framed to protect the interests of investors,
(b) strict rules and regulation for listing of securities. In case the brokers adopt any malpractice in their dealings, their membership may be suspended for some time or cancelled or fine may be imposed.

Question 8.
Enumerate the sales promotion .
Answer:
Sales Promotion has defined by various authors as under :

1. L.KJohnson : “Sales Promotion consists of all those activities whose purpose is to supplement,to coordinate and to make more effective the efforts of the sales force,of the advertising department and of distributors and to increase sales and otherwise stimulate consumers greater initiative in buying.”
2. American Marketing Association : “Sales promotion comprises those marketing activities,other than personal selling,advertising and publicity that stimulate consumer purchasing and dealer effectiveness,non -recurrent selling efforts not in the ordinary routine.”
3. Luick and Zeiler :”Sales promotion as a tool of markets promotions gives rise to increase in product usage as well as expansion of markets for a product or introduction of a new product.”

Question 9.
Explian the four functions of management.
Answer:
The four functions of management are as follow :

(i) Planning : Planning is the function of determining in advance what is to be done and who is to do it. This implies setting goals in advance and developing a way of achieving them efficiently and effectively. Planning cannot prevent problems but it can predict them and prepare contingency plans to deal with them if and when they occur, .

(ii) Organising : Organising is the management function of assigning duties, grouping tasks, establishing authority and allocating resources required to carry out a specific plan. It determines what activities and resources are required. It decides who will do a particular task, what it will be done, and when it will be done. Organizing involves the grouping of the required tasks into manageable departments or work units and the establishment of authority and reporting relationships.

(iii) Staffing : Staffing is finding the right people for the right job. A very important aspect of management is to make sure that the right people with the right qualifications are available at the right places and times to accomplish the goals of the organisation. This is also known as the human resource function and it involves activities such as recruitment, selection, placement and training of personnel.

(iv) Directing : Directing involves leading, influencing and motivation employees to perform the tasks assigned to them. This requires establishing an atmosphere that encourages employees to do their best motivation and leadership are two key components of direction. Directing also involves communicating effectively as well as supervising employees at work. Motivating workers means simply creating an environment that makes them want to work.

Question 10.
Write short notes on function of financial management ?
Answer:
The finance all manager in order to achieve the objectives of financial management, performs many functions. These functions involve many financial decisions which may be discussed under two groups.

(a) Principle functions
(b) Supplementary functions.

(a) Principle functions :
These are the types of principle functions :

1. Estimatiay the financial Requirements
2. Decision a bout capital structure,
3. Dividend Devisions.

(b) Supplementary functions:
These are the types of supplementary functions :

1. Cash management,
2. Report with Investors
3. Stock Exchange Trends.

Question 11.
What are the advantages of partnership ?
Answer:
The advantages of partnership are as following :

1. Easy to starts : There is no complicated legal procedure to start partnership. It does not take much expenditure to start partnership. It can be started very easily.
2. Sufficient capital: Partnerhsip has more capital resources as compared to sole trade. It can even get Model larger amount of loans from other institutions on easy terms.
3. More resources : The partnership has resources, contributed by at the most ten persons in banking and twenty persons in other busness. It is also the combination of the talent of many persons, working as partners.
4. Specialization in management : A division of work in partnership is done in accordance with scientific management principles.
5. Balanced decision : Decisions are taken jointly by consulting each other, therefore, the partnership is able to take balanced decision.

Question 12.
Discuss the four points of marketing.
Answer:
The four points of marketing are :

1. Product
2. Price
3. Place
4. Promotion and are discussed as below :

(i) Product : Product means goods or services or ‘anything of value’, which is offered to the market of for exchange.
For example : Hindustan Lever Company offers, number of consumer products like toiletries (close- up, tooth paste, lifebuoy, soap ec.) The important product decisions include decisions about the features, quality, packaging, lebelling and branding of the products.

(ii) Price : Price is the amount of money customers have to pay to obtain the product. The marketers have not only to decide about the objectives of price sitting but to analyse the factors determining the price and fix a price for the firm’s products.

(iii) Place : Place or physical distribution include activities that make firm’s products available to the target customers. Important decision areas in this respect include selection of dealers or intermediaries to reach the customers, providing support to the intermediaries. The other decision areas relate to managing inventory, storage and warehousing and transportation of goods from the place it is produced to the place it is required by the buyers.

(iv) Promotion : Promotion of products and services include activities that communicate availability features, merits etc. of the products to the target customers and persuade them to buy it. The promotional activities and spend substantial amount of money on the promotion of their goods through using number of tools such as advertising, personal selling and sales promotion techniques (like price discounts, free samples, etc.)

Question 13.
What is money market ?
Answer:
Enterprises need money, both for short medium and long’term. Medium and long medium and long term funds are raised in the capital market.
Short term funds are collected from the money market, short term means less than one year. Thus, money market is the market that facilitates the procurement of funds for short term or current requirements.
Some are the tools of money market-

1. Treasury Bill
2. Inter bank call money
3. Commercial paper
4. Certificate of Deposits
5. Trade bill / commercial bill

Question 14.
Define business company.
Answer:
The formation of a joint-stock company in India is to be done as per rules and guidelines envisaged in the companies act 1956. The meaning of companies business related with joint stock companies. Joint stock companies are made for profit and it is a optional institution which capital are undistributed in transferable shares. That is the mean it anybody can sell and purchase its share. The liabilities of the members are limited and general. It has a fixed existence and it is a artificial person and it is formed by common seal.

Question 15.
What are source of credit marketing ?
Answer:
In business the question of credit creditability is of almost significance in turns of an entrepreneur’s efforts on the basis of which the financial agencies and the businessman remain loyal and omitted to each other. This creditability is built on the basis of the business-man discipline creditability is achieved with a lot of efforts and difficulties and no remedy is available when it is lost. The transaction of the goods in the parties on the basis of commercial credit. It is called credit-marketing.

The sources of credit marketing are different type for example shares, debentures, banking companies and financial institutions from these sources traders get finance.

Question 16.
What is the role of profit/advantages in business.
Answer:
Roal of business should be profit maximisation some points are as follows :

1. Profit is the reward of labour.
2. Profit is the means of the satisfaction of human needs.
3. It is a measure of business efficiency.
4. Profit is the base of business protection, growth and stability.
5. Profit is the base of social responsibilities.
6. Profit is the cause of extension of various economies.
7. Profit is the base of exchange.
8. Profit is an incentive.

Question 17.
What is importance of consumer protection ?
Answer:
Consumer protection has a wide agenda. Importance of consumer protection from the consumers point of view.
Importance of consumers protection from the point of view of business are as follows :

1. Long-term interest of business : Satisfied customers not only lead to repeat sales but also provide good feedback to prospective customers and thus, help in increasing the customer base of business.
2. Business uses society’s resources : Business organisations use resources which belong to the society. They thus, have a responsibility to supply such products and render such services which are in public interest.
3. Socila Responsiblity : A business has social responsibilities towards varousnterest groups. Business organisations make money by selling goods and providing services to consumers.
4. Moral jusuficaPon : It is the moral duty of any business to take care of consumer’s interest and avoid any form of their exploitation. Thus, a business must avoid unscrupulous, exploitative and unfair trade practices like defective and unsafe products, adulteration, false and misleading advertising, hoarding, black marketing etc.

Question 18.
Explain the importance of financial planning in modern age.
Answer:
The importance of financial planning can be explained as follows:

1. It tries to forecast what may happen in future under different business situations
2. It helps in avoiding business shocks and surprises and helps the company in preparing for the future
3. If helps in co-ordinating various business functions e.g.sales and production functions,by providing clear policies and procedures
4. Detailed plans of action prepared under financial planning reduce waste,duplication of efforts, and gaps in planning
5. It tries to link the present with the future
6. It provides a link between investment and financing decisions on a continuous basis
7. By spelling out detailed objectives for various business segments,it makes the evaluation of actual performance easier.

Question 19.
Discuss the importance of communication in any business organisation.
Answer:
It is rightly said that managerial functions cannot be carried out without an efficient system of communication.We can give following arguments in favour of our decision:

1. Better coordination : Communication serves as a tool for coordinating activity.Coordination without communication is a remote possibility.Through communication employees come to know what is going on in other departments.
2. Quick decision and its enforcement : effective communication is needful for the quick
   decision.Effective communication translates the policies into effective instrument of seeing through the organisation on the veil of its progress.Effectiveness of the policies can be judged from its success which surely depends on effective communication system.
3. High morale of the employees : The effective medium of the communication develops the feeling of mutual trust.Hence,workers offer their proposals,suggestions and ideas.If suggestions of the workers are properly cared and promoted ,they will feed proud.All these help in boosting morale of the employees.

Question 20.
Explain the social responsibilities of the management.
Answer:
Social obligations means the responsibility of business to act in a manner which will serve the best interest of the society. The following are the various points which is need for assumption of social responsibilities :

1. Long-term business interest: While a business must seek to maximize profits and wealth, it must not igonre social and human problems of the society. Business is an important part of the society.
2. Government Intervention : The Government has favorable attitude towards business which fulfill their social obligations. Laws to prevent unfair trade practices, black marketing, overcharging, adulteration etc. bear proof of this.
3. Use of society’s resources : Business is a creation of the society and so it should respond to the requirements of the society. It is essential that every business enterprise should fulfill its social responsibilities.
4. Public image : If a business is conscious of its social responsibilities it will certainly enjoy a favorable image and will retain the needed credibility with the public.
5. Moral justification : Every business uses capital, physical, human resources of the society for business purposes.

Question 21.
Explain the various structures of organisation.
Answer:
The various forms of business organisations which is discussed follows :
(a) Sole proprietorship
(b) Joint hindu family business
(c) Partnership
(d) Cooperative societies and
(e) Joint stock company

(a) Sole proprietorship : Sole proprietorship is simple form of organisation. It is said that this organisation was evolved at the time when the man started living in family. As the time changed its shape and size went on changing. Only that person is responsible for its profits and losses. and services, creates employment opportunities, adopts new technology for the greater good of the people and leads the path towards growth and developments.

Long Answer Type Questions

Question no. 26 to 33 are Long answer type questions. Answer any 4 of them. Each question carries 5 marks. (4×5 = 20)

Question 26.
“Money spent on advertising is a waste.”Do you agree with this view ? Give reasons in your answer.
Answer:
“Money spent on advertising is a waste.” We do not agree with this statement.The given statement is based on the following agreements :

1. Advertising makes people to buy things which they do not really need.
2. Advertising destroys utilities of old models already in used.Advertising introduces new products with modern technology.For example with the introduction of colour television,black and white TV,become unpopular.
3. Advertising leads to discontent in the minds of those people who are temperate to purchase advertising goods but are not able to do so because they cannot afford to buy.
4. The cost of advertisement has to be borne buy the consumers.
5. Advertising tends to develop monopolices which are not desirable from social point of view .For example ,Daldavanaspati ,coalgate toothpaste ,lux toilet soap etc.have so much monopolised the market that is very difficult new manufactures to complete with these products.
6. Advertising is morely degrading .Advertisement excessive use of outrangingssetiments ,exciting .emotions nude poses of fair sex.They lower down the calculater and moral based of the new younger generation. However,abovecritictism are exaggerated and ill- founded.Advertising performs the number of economics function .Advertising leads to increase sales and helps the firm to produce on a large scale. It creates more business and it rises the standard of leaving. The utility of advertisement has proven. lt immense need to modern business and therefore we cannot say that all advertising is unnecessary and wasteful.

Question 27.
What do you mean by Entrepreneurship ?Explain any three needs of entrepreneurship.
Answer:
Entrepreneurship is a skill,a view- point ,a thinking, a technique and a working procedure. Entrepreneurship means he capability and tendency to bear risks involved in industry and business.Entrepreneurship is an art ,a tact .view point .thought and technique.Entrepreneurship is a group behavior and knowledge based activity.Following are the three needs of entrepreneurship :

1. Resource mobilizations : After getting appraisal from funding agents,entrepreneur starts identifying and assessment of various resources that are needed as inputs to produce the desired output.The types of resources to be taken care of will include:
   • Materials
   • Money
   • Machines
   • Market availability
   • Technology and
   • Human resources Entrepreneurs try their best to get these resources at minimum cost.
2. Scanning the environment : The process of setting up of an enterprise begins with the scanning of business opportunities.To scan business opportunities entrepreneur depends upon personal observations .personal and professional contacts.reports of governments and other official documents,Discoveries of new products .published documents etc.
3. Development of product of product/ service : Scanning of business environment helps the businessmen to know the opportunities available.For example, on scanning Indian and international environment one can find that due to liberalization in trade policy there is more scope, of external trade but exactly which product to export/import in which quantity,at what price,to which country ,etc.are the next decisions businessman has to take.

Question 28.
“Human beings cannot be only motivated through monetary incentives,non -incentives,non – monetary incentives are also necessary for motivate them.” Explain about non-monetary incentives in this context.
Answer:
Financial incentives are used to motivate employees for higher work.However,individuals have various needs which they want to satisfy while working in an organisation.People at comparatively higher level of managerial hierarchy attach more importance to socio- physycological needs which cannot be satisfied by money alone.

They want status and recognition in society;they want to satisfy there ego needs and they want to achieve something in their lives,thus .management ,in addition to the financial incentives provides non -financial incentives to motivate people in the organisation.

Forms of Non -financial Incentives: In order to motivate the employees .management may use the following forms of non-financial incentives:

1. Praise of appreciation of work done : Recognition of satisfactory performance acts as a non- financial incentive since it satisfies one’s ego needs.However,this incentive should be used with great care because praising an incompetent employee creates resentment among competent employees.
2. Workers’ participation in management : Participation in management provides strong motivation to the employees.Gives them psychological satisfaction if there voice is heard participants in management provides for two ways communication and so imbibes a sense of importance
3. Suggestion system : Suggestion system is an incentive with satisfies many needs of the employees. Many organisations which use the suggestion system make use of cash awards for useful suggestion .They sometimes publish the workers name with the photograph in the company magazine.This motivates the employees to be in search for something which may be of greater use to the organisation.
4. Competition : If there is healthy competition among individual employees ,group of employees ,it leads them to achieve their personal or group goals.Hence,competition acts as none financial incentives.
5. Opportunity for growth : Opportunity for growth is another kind of intensive.If the employees are provide opportunity for their advertisement and growth to develop their personality,they feel very much satisfied and more communicate to organisation goals.

Question 29.
Explain the sub-clause of Memorandum of Association.
Answer:
The memorandum of association contains the following clauses :
(i) Name clauses : Under this clause, the name of the company is stated. Any suitable name may be chosen subject to the following restrictions :

• The name of the company must not directly or indirectly incude the word ’President”, “King”, “Queen”, “Emperor”, “National Flag”, “Small soale” and cottage Industriesd”, “Federal”, “Municipal”, “Provincial” etc.
• It must not be objectionable under the provisions of the emblems, and names.
• It should not be identifcal with or resemble the name of any existing company.
• The proposed name should not be objectionable in any other manner. It must not hurt the feelings of any section, of the society.
• The name of a public company should end with the word “Limited”. In case of private company. The name should end with “Private Limited”.
• The name has to be displayed on every letter pad or any poster or display of the company.

(ii) Domicile clause : In this clause, name of the state in which the registered office of the company is to be situated is mentioned. Domicile clause is important as it determines the jurisdiction of the court.

(iii) Object clause : It is the most important clause of Memorandum of Association. It defines the limits and scope of the operations of the company. The object clause must specify the objects of the company in the following order :

• The main object of the company to be pursued by the company on its incorporation and the objects incidental to the attainment of the main objects
• Other object of the company not included in the above clause.

(iv) Liability clause : The fourth clause must state whether liability of the members is limited if so, whether it is limited by shares or by guarantee. In a company limited by guarantee, the liability clause will state the amount which each member, shold undertake to contribute to the assets of the company in the event of liquidation of the company.

(v) Capital clause : This clause, states the amount of capital, with which the company is registered, unless the company is an unlimited company. The shares into which the capital is divided must be of fixed value, which is commonly known as the nominal value of the share, the capital is variously described as “nominal”, “authorised” or “registered”. The company cannot issue shares without altering the memorandum as provided by section 94 of the companies act, 1956.

(vi) Association clause : The memorandum concludes with the subscription clause in which there is a declaration of association. The subscribers to the memorandum declare :

“We, the several persons whose names and addresses subscribed, are desirous of being formed into a company in pursuance of this memorandum of association, and we respectively agree to take the number of shares in the capital of the company set opposite our respective names.”

Then follow the names, addresses, occupations of the subscribers, and the number of shares each subscriber has taken and his signatures attested by a witness

Question 30.
Discuss the importance and methods of training.
Answer:
The importance of training are as follows :

1. Training is a systematic learning, always better than hit and trial methods which lead to wastage of efforts and money.
2. Training increases, employee morale and reduces absenteeism an employee turnover.
3. Improved skills and knowledge due to training lead to better career of the individual.
4. Training makes the employee more efficient to handle machines. Thus, less prone to accidents.
5. It helps in obtaining effective response to fast changing environment technological and economic.

There are various methods of training. These are broadly categories into two groups : On the job and off-the job methods.

On the job methods :

1. Apprenticeship programmed : Apprenticeship programmes put the trainee under the guidance of a master worker. These are designed to acquire a higher level of skill.
2. Coaching : In this method, the superior guides and instructs the trainee as a coach. The coach or counseler sets mutually agreed upon goals.
3. Internship training : It is a joint programmer of training in which educational institutions and business firms cooperate.
4. Job rotation : This kind of training involves shifting the trainee from one department to another or from one job to another.

Off the job methods :

1. Class room lectures/conferences : The lecture or conference approach is well adapted to conveying specific information rules, procedures or methods.
2. Films : They can provide information and explicitly demonstrate skills that are not easily represened by the other techniques.
3. Case study : Taken from actual experiences of organisations, cases represente attempts to describe, as accruetly as possible real problems that managers have faced.
4. Computer modelling : It simulates the work environment by programming a computer to imitate some of the realities of the job and allows learning to take place without the risk or high costs.
5. Vestibule training Employees learn their jobs on the equipment they will be using, but the training is conducted away from the actual work floor.
6. Programmed instruction : The method incorporates a prearranged and proposed acquisition of some specific skills or general knowledge.

Question 31.
Explain the long term financial sources in business.
Answer:
The financial requirements of a company may be classified as :

1. Long term finance
2. Medium term
3. Short term finance.

(i) Long term finance : Long term finance required for five years and above. Such finance is used for investment in fixed assets such as land, building, plant and machinery, furniture etc. Fixed assets are those assets which are required for permanent use and are not meant for sale. Long term finance is raised from shareholders, debenture holder, financial institutions and retained earnings.
Following are the main sources of long term finance :

1. Issue of shares : ‘Share’ is a share in the share capital of a company. According to section 2(46) of the companies act, “A share is the share in the capital of a company and includes stock except where a distinction between stock and share is expressed or implied.”
2. Issue of Debentures : A debenture is an instrument issued under the common seal of the company, acknowledging its debt to the holder under the terms and conditions specified in the instrument.
3. Ploughing back of profit or retained profit: Ploughing companies do not generally distribute the whole amount of profits as dividend.A certain proportion is transferred to reserves and utilised as additional capital. Thus, the financial needs of a company can be yet by retaining a part of the annual profits.
4. Loans from specialised financial institutions Loan when a bank mokes an advance in lump-sum against some security. The entire loan amount is paid to the borrower either in cash or by credit to his account, financial institutios have been set up of all India and regional levels for accelarating the growth of industries. These are mainly IFCI, ICICI, SECs, IDBI, SIDFCs, LIC, and UTI.

Question 32.
“Authority can be delegated ,but not responsibility.” Explain.
Answer:
“Authority can be delegated ,but not responsibility.” This statement is explaining about importance of delegation.Delegation or Authority is a process of sharing of tasks and authority between a manager and his subordinates.Delegation of authority is defined by Allen in the following words, “Delegation is the process a manager follows in dividing the work assigned to him so that he performs that part which only he,because of his unique organisational placement ,can perform effectively,and so that he can get others to help him with what remains.”
The following are the advantages of delegation or authority :

(i) Reduces the workload of managers : Delegation of authority permits a manager to share his workload with his subordinates. By passing on some of his own work to the subordinates,the manager is able to concentrate on more important aspects of his work-When delegation or authority takes place at all levels of the organisation it facilitates proper division of managerial work and its assignment to all managers in a systematic manner.

(ii) Basis of superior – subordinate relations : Delegation is the process by which superior – subordinate relations among managers are established.The flow of authority from the top management to lower levels is directed and regulated by the process of delegation.

(iii) Improves managerial effectiveness : In the delegation process managers pass routine work to the subordinates so they are free to concentrate on other important matters.The main job of managers is to get the work done effectively and by delegating the authorities and responsibilities.

(iv) Motivates subordinates : In the delegation when the manager is sharing his responsibilities and authority with the subordinates it motivates the subordinates as they develop the feeling of belonging and trust which is shown to them by their superiors.

(v) Facilitates the development of managers : Delegation is a source of development of managers.lt opens up opportunities for managers to acquire leadership and other skills and competency.They are required to exercise theirauthority,to handle situations and to solve managerial problems.

(vi) Facilitiesorganisational growth : In the process of delegation when the managers are passing their responsibility and authority to the subordinates they keep in mind the qualification and capability of all the subordinates.

Question 33
Mention the different external sources of recruitment.
Answer:
Anorganisation must recruit employeesfromoutside, i.e. through external sources.The important external sources of recruitment are as given follow :

(i) Factory gate : For recruitment of semi – skilled and unskilled employees a notice is put at the factory gate specifying the requirement of various types of workers.Job seekers wait outside the factory gate in the hope of finding some employment.

(ii) Waiting list: Very often organisations prepare and maintain a waiting list of employees from the applications of those candidates who had applied but could not be selected.

(iii) Employees recommendations : A large number of organisations ask their present employees to recommend the names of suitable candidates as and when a vacancy arises.The employees feel happy to recommend the names of their relatives and friends and ask them to apply for the jobs which suit them.

(iv) Labour union recommendations : It is a common practice in some organisations to ask the labour union(s) leaders to recommend the names of suitable candidates for the vacancies to be filled in the organisation.The leaders feel happy to suggest the names of suitable candidates.

(v) Private placement agencies : These are of recent origin now a days reputed private placement agencies such as Tata Consultancy Services are doing commendable jobs in this field.The agencies maintain data bank of specialists in various fields – skilled ,semi – skilled and even unskilled employees.

(vi) Employment Exchanges : Employment Exchanges have been set up by the government in metropolitan and other big other cities.People seeking employment get registered with the employment Exchange nearest to their place of residence.

(vii) Media advertisement: By far advertisement in leading newspaper,magazines and journals is a widely used method of external recruitment for skilled and specialisedjobs.lt is very effective due to the wide circulation.

(viii) Collages,institutions and campus: Reputed and multinational companies are recruiting employees through campus recruitment’ at reputed business schools,colleges and particularly at 1.1.Ms. Reputed institutions have 100% placements of their students.

Bihar Board 12th Business Studies Model Papers

Bihar Board 12th Business Studies Model Question Paper 3 in English Medium

Time : 3 Hour 15 Min
Full Marks : 100

Instructions

1. Candidates are required to give their answers in their own words as far as practicable.
2. Figures in the right hand margin indicate full marks.
3. 15 minutes of extra time has been allotted for the candidate to read the questions carefull.
4. This question paper has two sections : Section -A and Section-B.
5. In Section-A, there are 50 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with black/blue ball pen against the correct option on OMR Sheet provided to you. Do not use Whitener/ Liquid/Blade/Nail on OMR Sheet, otherwise the result will be treated as invalid.
6. In Section-B, there are 25 Short answer type questions, out of which any 15 questions are to be answered. Each question carries 2 marks. Apart from this, there are 08 Long answer type questions, out-of which any 04 of them are to be answered. Each question carries 5 marks.
7. Use of any electronic device is prohibited.

Objective Type Questions

Question No. -1 to 50 have four options provided, out of which only one is correct. You have to mark, your selected option, on the OMR-Sheet. Each question carries 1 (one) mark. [50 x = 50]

Question 1.
“A Plan is a trap to capture the future.” This statement is of
(a) Newman
(b) Hurley
(c) Allen
(d) Terry
Answer:
(c) Allen

Question 2.
According to George R. Terry, the types of planning are-
(a) 08
(b) 06
(c) 04
(d) 02
Answer:
(c) 04

Question 3.
Planning is for
(a) Present
(b) Future
(c) Past
(d) All
Answer:
(b) Future

Question 4.
Planning is
(a) Necessary
(b) Un necessary
(c) Wastage of time
(d) Wastage of money
Answer:
(a) Necessary

Question 5.
Of all mangerial activites planning is the
(a) Beginning
(b) End
(c) Beginning and End
(d) None of Those
Answer:
(a) Beginning

Question 6.
Father of scientific management was-
(a) Taylor
(b) Urbick
(c) Henry Fayol
(d) Kimbell
Answer:
(a) Taylor

Question 7.
Which of the following statement is inconsistent ?
(a) Management is purposeful
(b) Instinct process
(c) Universal
(d) Not separate from ownership
Answer:
(b) Instinct process

Question 8.
Henry Fayol’s principles of management are-
(a) 05
(b) 10
(c) 14
(d) 16
Answer:
(c) 14

Question 9.
When scientific management was introduced ?
(a) 1913
(b) 1832
(c) 1903
(d) 1920
Answer:
(a) 1913

Question 10.
By scientific management workers get-
(a) Advantage
(b) Disadvantage
(c) None
(d) Both Advantage & Disadvantage
Answer:
(a) Advantage

Question 11.
Wages given to workers in traditional management was-
(a) Low
(b) High
(c) Maximum
(d) Normal
Answer:
(a) Low

Question 12.
The experiment done by Taylor under scientific management were-
(a) Motion Study
(b) Fatigue Study
(c) Time Study
(d) All
Answer:
(d) All

Question 13.
Mental revolution is the essence of-
(a) Scientific Management
(b) Combination
(c) Rationalisation
(d) Profession
Answer:
(a) Scientific Management

Question 14.
Henry Fayol was born in-
(a) Japan
(b) France
(c) Germany
(d) America
Answer:
(b) France

Question 15.
Principles of management are-
(a) Universal
(b) Flexible
(c) Dynamic
(d) All of these
Answer:
(c) Dynamic

Question 16.
Development of employees involve-
(a) Transfer
(b) Promotion
(c) Training
(d) All
Answer:
(d) All

Question 17.
Methods of Training are-
(a) Conference
(b) Lectures
(c) Apprenticeship
(d) All of the above
Answer:
(d) All of the above

Question 18.
Employees training is-
(a) Unnecessary
(b) Necessary
(c) Compulsory
(d) Luxury
Answer:
(c) Compulsory

Question 19.
Money spent on staffing is-
(a) Necessary
(b) Wastage
(c) Investment
(d) None of these
Answer:
(c) Investment

Question 20.
Human Resource Development includes-
(a) Recruitment
(b) Selection
(c) Training
(d) All of these
Answer:
(d) All of these

Question 21.
Main elements of direction are-
(a) 02
(b) 03
(c) 04
(d) 06
Answer:
(c) 04

Question 22.
Direction is related to employees
(a) Top Level
(b) Middle Level
(c) Lower Level
(d) All Level
Answer:
(d) All Level

Question 23.
Direction is
(a) Compulsory
(b) Necesssary
(c) Unnecessary
(d) Wastage of time
Answer:
(a) Compulsory

Question 24.
Supervision is
(a) Necessary
(b) un nesessary
(c) Wastage of time
(d) None of these
Answer:
(a) Necessary

Question 25.
For Stock exchange the service of SEBI is
(a) Volntary
(b) Nessary
(c) un necessary
(d) Compulsory
Answer:
(d) Compulsory

Question 26.
Marketing includes-
(a) Purchase
(b) Sale
(c) Warehousing
(d) All of the above
Answer:
(d) All of the above

Question 27.
Which one is not the consumer product among the following ?
(a) Raw materials
(b) Refrigerator
(c) Old statues
(d) Shoes
Answer:
(c) Old statues

Question 28.
Essentials of a good brand are-
(a) Short name
(b) Easy to remember
(c) Attractive design
(d) All of these
Answer:
(d) All of these

Question 29.
Labelling is compulsory in packed consumer products- ”
(a) All
(b) A Few
(c) None
(d) None of the above
Answer:
(a) All

Question 30.
Co-ordination is-
(a) Voluntary
(b) Necessary
(c) Unnecessary
(d) Wastage of time
Answer:
(b) Necessary

Question 31.
Co-ordination is established by-
(a) Highest level management
(b) Medium level management
(c) Low level management
(d) None of these
Answer:
(c) Low level management

Question 32.
According to George R. Terry the functions of management are-
(a) 02
(b) 04
(c) 06
(d) 07
Answer:
(b) 04

Question 31.
Co-ordination is established by-
(a) Highest level management
(b) Medium level management
(c) Low level management
(d) None of these
Answer:
(c) Low level management

Question 32.
According to George R. Terry the functions of management are-
(a) 02
(b) 04
(c) 06
(d) 07
Answer:
(b) 04

Question 33.
The essence of management is-
(a) Co-ordination
(b) Organisation
(c) Staffing
(d) Controlling
Answer:
(a) Co-ordination

Question 34.
The nature of management is-
(a) As an inborn ability
(b) As an acquired ability
(c) As inborn ability & as an acquired Ability both
(d) None of these
Answer:
(a) As an inborn ability

Question 35.
Management is,
(a) Art
(b) Science
(c) Art and science both
(d) Profession
Answer:
(c) Art and science both

Question 36.
Which of the following attitudes is not generally associated with successful entreprenenship ?
(a) Competition and co-operation
(b) Desire to influence others
(c) Innovation and product improvements
(d) Staticity in business
Answer:
(b) Desire to influence others

Question 37.
Physical distribution does not include-
(a) Transportation
(b) Financing
(c) Warehousing
(d) Inventory control
Answer:
(b) Financing

Question 38.
Which is not an element of promotion mix ?
(a) Advertisements
(b) Personal selling
(c) Sales promotion
(d) Product development
Answer:
(a) Advertisements

Question 39.
Advertisement is deemed as-
(a) Wastage
(b) Investments
(c) Luxury
(d) None of these
Answer:
(b) Investments

Question 40.
Objectives of sales promotion are-
(a) To introduce with new products only
(b) To attract new customers only
(c) To counter competitor only
(d) All the above
Answer:
(d) All the above

Question 41.
New economic policy was declared in
(a) July 1990
(b) July 1991
(c) July 1992
(d) July 2001
Answer:
(b) July 1991

Question 42.
National Commission can settle disputes
(a) up to Rs.5 lakhs
(b) up to Rs.10 lakhs
(c) up to Rs.15 lakhs
(d) above Rs.l crore
Answer:
(c) up to Rs.15 lakhs

Question 43.
Management is a profession.” This statement is of
(a) George R. Terry
(b) American Management Association
(c) Henry Fayol
(d) None of these
Answer:
(b) American Management Association

Question 44.
Control is the _________ function of the management.
(a) first
(b) Last
(c) Third
(d) second
Answer:
(b) Last

Question 45.
Which of the following is related with social environment ?
(a) Composition of families
(b) Consumer Protection Act
(c) Business Law
(d) Privatisation
Answer:
(a) Composition of families

Question 46.
The feature of a good plan is
(a) Expensive
(b) Time consuming
(c) Flexible
(d) Rigid
Answer:
(b) Time consuming

Question 47.
Co-ordination is established by
(a) Top level management
(b) Middle level management
(c) Lower level management
(d) none of these
Answer:
(b) Middle level management

Question 48.
Marketing concept is
(a) Production co-oriented
(b) Sales – oriented
(c) Customer- oriented
(d) All of these
Answer:
(d) All of these

Question 49.
Fixed capital is needed for period.
(a) short period
(b) long period
(c) both (a) and (b)
(d) none of these
Answer:
(b) long period

Question 50.
Capital market deals in
(a) short – term funds
(b) medium term funds
(c) long term funds
(d) none of these
Answer:
(c) long term funds

Non-Objective Type Questions

Short Answer Type Questions

Question no. 1 to 25 are Short answer type questions. Answer any 15 out of them. Each question carries 2 marks. (15 x 3 = 30)

Question 1.
What is meant by recruitment ? How is it different from selection ?
Answer:
Recruitment-This means to search prospective candidates and to stimulate them to apply for jobs in an organisation.
Distinction between selection and recruitment :

1. Recruitment is inviting and procuring application where as selection is processing and screening applicants
2. Recruitment is a medium while selection is the end results
3. Recruitment is a positive process, while selection is a negative one.
4. The process of selection starts, where the process of recruitment ends.

Question 2.
What is critical point control ?
Answer:
Critical point control-Control can not be excercised at all points of an activity, as it may be time-consuming and very expensive. Managers should identify the important or critical points which must be looked after. If these critical points or Key Results Areas (KRAs) are properly controlled, the entire activity would be deemed to have been controlled. In a labour-oriented industry, for example, 10% increase in wages will be more deterimental for the enterprise than .the amount to be spent for the purchase of furniture and crockery for the worker’s canteen.

Question 3.
What are the objectives of SEBI ?
Answer:
The followings are the objectives of SEBI:

1. To protect the investers’ interest in securities
2. To promote and develop securities market
3. To develop code of conduct for intermediaries like brokers, merchant bankers etc.
4. To mobilise and allocate resources through securities market
5. To provide facilitate of competitive, professionalized and expanding market to the intermediaries.

Question 4.
How does planning make controlling possible ?
Answer:
Planning make controlling possible by using these types of plans :

1. Corporate plans
2. Functional Plans
3. Short – term plans
4. Long – term plans
5. Standing plans

Question 5.
Give suggestions to make advertising ‘ more effective.
Answer:
Advertising is the preparation and communication of some message to the desired population through a medium/media,regarding a product, service or idea for some consideration.
Consider following term to making advertising more effective :

1. Maintenance of quality
2. Helps in making decision
3. Educating customers
4. Aids press
5. Encouragement to research
6. Higher standard of living
7. Creation of goodwill

Question 6.
Indian Government has made many laws to secure the interests of consumers. Discuss.
Answer:
Some important Consumer Protection Act made by Indian Government as discussed below-

1. The Prevention of Black Marketing and Maintenance of Supplies of Essential Commodities Act., 1980-This Act prevents social and economic evil of black marketing. Any person engaged in black marketing can be detained under this Act.
2. The Essential Commodities Act, 1956-This Act provides for the control of production, supply, price and distribution of essential commodities, like wheat, rice, sugar, oil etc.
3. The Standard of Weights and Measures Act, 1956-This Act lays down that standards of measurement must be set whenever required. Inspection of weights and measures should be undertaken as some traders find ways of weighing or measuring less or weighing the containers along with the goods.
4. The Competition Act, 2002-This Act has been substituted with the Monopolies and Restrictive Trade practices Act, 1969 (MRTP Act, 1969).
5. The Contract Act, 1982-This Act binds the people to fulfill their promises with respect to a valid contract.
6. The Consumer Protection Act, 1986-The object of this Act to protecting the consumers from anti trade practices making profit.

Question 7.
What is the importance of management ?
Answer:
If the administration of the organised sector is left to generalists, having no knowledge of management theory and practice, the activities of business and non-business organisations will be Jeopardised and there will be chaos all around. If a nation wants to be prosperious, it will have to produce efficient managers.

The following are the importance of efficient management:

1. Maximum results with minimum Resources
2. Realisation of Personal objectives,
3. Economic Growth
4. System in place of Rule of Thumb
5. Protection of Investor’s Interests.

Question 8.
“Planning is a mental process.” Explain.
Answer:
Let us examine some of the parts of definition of planning in regard “Planning is a mental process”.-
“Planning is deciding in advance what to do, how to do it, when to do it and who is to do it. It makes possible for things to occur which would not otherwise happen : we can also say that planning is the excercise of creative thinking in the solution of business problems. It involves the determination of what is to be done, how and where it is to be done, and who shall be responsible. We conclud the above fact that The act of thinking and determining a course of action, spelt out in detail, is called planning.

Question 9.
What do you mean by ‘training’ ? How does it differ from ‘education’ ?
Answer:
Training is the process of improving the attitudes, skills, performance and knout edge of the employees to make them enable for the job. Training is different from education on the basis of following grounds –

1. Education focuses on creating lifelong independent thinkers where as training focuses on skills sought after by employers.
2. Training has its roots in the guid system while education’s origins lie in universities.
3. Training uses textbooks and prescriptives methods.
4. In today’s universities highly specialized areas of training are being bassed off as education.

Question 10.
State the objectives of controlling.
Answer:
The purpose of managerial control is to ensure the desired level of efficiency in business. It helps the manager to achive the desired goals of business efficiently and effectively. The objectives of controlling are briefly stated below :

1. To develop suitable control techniques and to diagnose critical control points
2. To ensures that the performance is in accordance with the predetermined plans or targets, and to know the actual level of performance,
3. To find out deviations from the planned schedule and targets
4. To analysis deviation for knowing causes there of.
5. To consider and take whatever correchive measure are necessary and to redefine standards, if deviations are uncontrollable.

Question 11.
Distinguish between marketing and selling.
Answer:
Marketing and selling can be distinguished on the basis of the following points :
Marketing :

1. It creates demand, products goods and services, supplies the same and satisfies the consumers.
2. It includes creation of demand, pricing, promotion, sales and after sale services.
3. It aims at optimizing profit by optimizing consumers’ satisfaction.
4. It start much earlier than that of selling and it continues even after selling has come to an end.

Selling :

1. It just transfers the ownership of goods and services to the consumers.
2. It involves giving of goods and services for some consideration.
3. It’s main objective is to maximising profits by maximising sale.
4. It start when the goods and services are ready for exchanging; it comes to an end when the owner ship is passed on to the buyer.

Question 12.
What do you mean by levels of Management ?
Answer:
‘Levels of Management’ means different categories of managers having different quanta of authority form the lowest to the highest. There is no hard and fast rule about the number of levels in an enterprise. Small organisations have less levels and the number of levels, generally, increases as the size of organisation expands. It is also not necessary that the enterprises of the same size should have equal or identical levels.
From the study point or view the various managers may be grouped into the following thrice levels.

1. Top level management.
2. Middle level management.
3. Lower level management or super-visory or operational level management.

Question 13.
Write the different steps in the process of organising.
Answer:
Organising as a process includes the following steps:

1. Identification of Activities and their division : The process of organising starts with the identification of various activities. These activities are divided into various homogeneous units, which is called job and these jobs are assigned to the employees in a manageable-and systematic manner.
2. Grouping the activities into departments : Each Cluster of homogeneous activities is eammarked as a department and it gets a name according to the activities under taken there.
3. Assigning Duties : Once departments have been created, employees working in different departments get the work to be done by them. Each employees gets the work according to his/her specialisation and skills.
4. Establishing work Relationship : Under this step various work relation ships are established. These may be senior subordinate or lateral relationship.

Question 14.
What is meant by capital structure ?
Answer:
Capital structure is the composition or mix of different types of long term capital whether owned or borrowed. These may be in the form of share capital, debentures and long term loans from financial institutions. Like the plan of capitalisation, capital structure should be also planned. Share capital is an important component of the capital structure.

Question 15.
Distinguish between Centralisation und Decentralisation.
Answer:
Centralisation & Decentralisation : Centralisation & Decentralisation are relation terms. An organisation is said to be centralised when the authority relation to decesion making is remained with top level while it is called decentralised when these authorities are delegated.

In the words of Henri fayol, Everything which goes to increase the sub-ordinate’s role, is decentralisation, everything that goes to reduce, it is centralisation.

Question 16.
Discuss in brief, any three principles of Scientific Management.
Answer:
Principles of Management :

1. Division of work : This means assigning the work to a person for which he is best suited. This principle is equally applicable to all hands of work managerial as well as technical.
2. Unity of command : This means that sub-ordinates should be receive orders from one senior only. A sub-ordinate receiving orders from two or more bosses can satisfy none.
3. Discipline : Disceplines mean the observance of rules and regulations this principle emphasises the obedience on the part of the sub-ordinates.

Question 17.
Give three advantages of budgetary control.
Answer:
There are following Advantage of Budgetory control:

1. Availcibility of yardsticks : Under budgetory control, budgets are used as yardsticks for determining the legitimacy of the task performed.
2. Maximum Utilisation of Resources : Various resources, like men, material, money etc. Can be optimally utilised through budgetory control.
3. Improvement in Co-ordination : It improve Co-ordination in the concerned activities for example, sale and production activities are interrelated.

Question 18.
Why is entrepreneurship regarded as a creative activity ?
Answer:
There are following reasons of entrepreneurship regarded as creative ativities as

1. It is necessary to management efficiently for its organisational ability and development.
2. For starting any new production.
3. For modify the organisation.
4. It is necessary for entrepreneur to development and competite their competitors.

Question 19.
Planning is a continuous process. How ? Explain.
Answer:
Planning is a continuous process : Plans need continuous review with a view to take cognisance of nature of economics to keep an equilibrium in changing pattern of demand and supply involving co-ordination of different function of management and thus to keep the business in perfect running conduction. So planning is a dynamic & continuous concept or process.

Question 20.
What do you mean by Promotion mix ?
Answer:
Promotion Mix : Promotion is an important element of marketing mix. It helps in boosting sales through its sub components.
There are four major promotion mix are :

1. Advertising
2. Personal selling
3. Sales promotion
4. Publicity.

The purpose of each is to popularize the product and services and help in boosting sales.

Question 21.
Distinguish between formal and informal communications.
Answer:
Distinguish between formal & informal communication
Formal communication :

1. It takes place in the formal fashion.
2. Communication takes place among officials or with outsiders in their capacity.
3. Parties involved in communication have formal relations.
4. Message is more reliable as the communication take place officially.
5. It consist information technology like cellphones, computers etc.

Informal communication :

1. It take place unofficially.
2. Communication takes place among official or with outsiders in unofficial capacity.
3. Here they have social or friendly relations.
4. Members communicate in their personal capacity sometimes inaccurate information may be passed on.
5. it consist face-to-face communication.

Question 22.
State any two functions of top level management.
Answer:
Following are the two function of top level management :

1. The main function of top level management is that to explain the objectives; determination of policy and directing.
2. It’s function to determine short-term or long term objectives of organisation.

Question 23.
Explain any two elements of delegation of authority.
Answer:
Following are the two elements of delegation of authority.

1. Assignments of tasks and duties : In the process of delegation every superior has to define the jobs to be performed by his subordination.
2. Grant of Authority : Grant of authority implies giving the rights to subordinates to decide and act, to use necessary resources and represents the superior.

Question 24.
What is Recruitment ?
Answer:
Recruitment functions is concerned with discovering the sources of man power required and tapping these sources, i.e. attracting the potential, employees to offer services to the working organisation.

Question 25.
Enumerate any four non-monetary incentives.
Answer:
Four-non-monetary incentive :

1. Safe services
2. Opportunity to promotion,
3. Eligibility, praise
4. Justice
5. Top enrichment
6. job security.

Long Answer Type Questions

Question no. 26 to 33 are Long answer type questions. Answer any 4 of them. Each question carries 5 marks. (4×5 = 20)

Question 26.
What is financial planning ? What are the element/factors which affect financial planning ?
Answer:
13. Financial planning-Financial planning means deciding in a advance how much to spend, on what to spend, according to the funds at your disposal. Walker and Baughn have defined financial planning in the following words-

“Financial planning pertains only to the function of finance and includes the determination of the firm’s financial objectives, formulating and promulgating financial policies and developing financial procedures.”
This definition is considered to be the best definition of financial planning. It includes three main aspects of financial planning-

1. Determination of financial objectives
2. Formulation of financial Policies
3. Development of financial procedures.

Factors Affecting Financial Planning Or, Elements Determining Financial Planning-A financial plan should be prepared very carefully because it has long-term impact on the working of an enterprise. Financial plan is affected by a number of factors. All these factors should be taken into consideration while preparing a financial plan-

(i) Nature of industry – The nature of industry of business plays a decisive role in drafting of financial plan. A capital-intensive industry like cement, paper or fertilizer requires more capital while a labour
intensive enterprise requires less amount of capital. In addition to it, the stability and regularity of income, future prospects of growth, the fluctuations in the demand of the product being manufactured by the firm, the extent of automation, etc., play a dominant role in determining the capital needs as well as capital structure.

(ii) Status of unit – This step includes the evaluation of increment characteristics of the unit like age, size, market area, scope and nature of the field, then reputation of management etc.

(iii) Flexibility – Flexibility and not the rigidity should be the main principle to be followed in the financing planning. If there is no flexibility in financial plans it would be very difficult later on, to carry on its expansion or diversification programmes due to lack of funds.

(iv) Plans for the future growth – Firms expect to grow larger in size as they grow old. So while undertaking current financing decisions, the factors of future growth should be suitable weighed. Capital structure must be of high grade securities.

(v) Capital structure – The capital structure of the company must be of high grade securities. It should be diversified but balanced. No permanant charge should be created on the capital of the industry. Fair rate of dividend should also be maintained.

(vi) Amount of risk – The risk involved in the business should also be discussed while planning the sources of funds. For business having more risks should issue ownership securities only while enterprise with stable earning expectation can take advantage of trading on equity.

(vii) Magnitude of external capital requirement – It would be a good policy for the industry to finance its expansion or diversification programmes through internal resources such as ploughing back of profits, reserves and surplus, etc., but short-term finances may be obtained from external sources by issuing redeemable preference shares or debentures if they are urgently needed.

(viii) Attitude of management – The attitude of management and management policies regarding trading on equity, capital earning ratio, the desire and extent to converse the control of enterprise, etc., affect in no small amount of pattern of financing.

(ix) Appraisal of alternative sources of finance – A study of the potential suppliers of fund has to be made and then Only a firm can expect to obtain funds suited to its advantage.

(x) Government policies and control – In preparing financial plan, the promoter should invariably take into account the governmental policies, financial controls and other monetary and fiscal policies of the government.

Question 27.
Explain various money market instruments.
Answer:
The main tools of money market have been described below-
(i) Treasury bills-These instruments are issued Reserve Bank of India. These are short-term securities with moturities of one year or less. These bills bear on interest. However they are issued at less than their face value and redeemed at for – the difference bring the interest on investment.

(ii) Interbank call money-This is a technique of lending and borrowing by banks on short-term basis. There may be situations when banks may come across shortage of money due to excessive withdraws or beary loan demands. In such cases banks can take loans from others banks as emergency solutions such loans are usually given for one day.

(iii) Commercial paper-This is a debt instrument issued by a company to meet its short-term financing needs. This is normally in the form of a promissory note. The issuing company promises to pay back the amount of the commercial paper within a stipulated period which is usually less than 270 days.

(iv) Certificates of deposit (CDs)-These were introduced in India in 1989 as a short-term unsecured promissary note, these are relatively low-risk debt instruments issued by banks. They mention that the named party has a specified sumon deposit, usually for a given period of time, at a fixed rate of interest, the period of CDs generally range from one month to five years. It implies that this sources in useful for short and medium-terms. Howevers, the permissible periodical range, at present, in India money market is from 7 to 365 days.

(v) Commercial bill/Trade bill – It is the bill of exchange drawn by the creditor on his/her debtors, extending credit for a short-term, it is a written order for a certain period to boy a specific sum for which the debtors has received value. After it has been signed by the debtors, it becomes a negotiable instruments. It can be discounted in a bank dr endorsed to a person against receipt of equivalent value or be kept till maturity and then getting the amount stated in it.

Question 28.
What do you mean by ‘Delegation’ ? Explain any four points which highlight the importance of delegation in an organisation.
Answer:
The need of delegation of authority arises when the volume is work of a manager increased and
be becomes over burdened. In order to reduce his work load, he follows a process by which some tasks within his Jurisdiction are assigned to his sub ordinates on a selective basis. For during the assigned work/ task, appropriate authority is also given. Such authority is known as delegation of authority.

Definitions : “Delegation is the process of a manager follow in dividing the work assigned to him so that he performs that part which only he, because of his unique organisational placement, can perform effectively and so that he can get others to help him what remains.”

Importance of delegation can be explained through the following points.

1. Relief to over burdned managers : As the business expand, seniors may become too heavily occupied. They may need the services of someone who can share their burden. They find the remedy by adapting the technique of delegation.
2. Improvement is the Quality and Quantity of works : When a single person has to do voluminous work, he does it at he cost of its quality and quantity. He can take care of both if he shares their work with someone. Delagation provides on opporunity to seniors for sharing their work with subordinates.
3. Source of Enhancing Job satisfactions : Delegation provides opportunities of Job-enlargement and Job-enrichment to sub-ordinates.
4. Seniors’ focus on more important Tasks : Seniors, generally, delegate the routine type of tasks to their delegates. This enables them to devote more time and energies to more important tasks.
5. Training ground for the sub-ordinates : Delegation provides opportunities to the sub-ordinates for doing higher level job.
6. Quick Decesion making : Since delegatees get limited tasks through delegation, they are able to take decisions quickly.
7. Effective co-ordination : Delegation stream lines the co-ordination and makes it more effective. All this makes co-ordination more effective.

Question 29.
“Money spent on advertisement is a social waste” Do you agree with this ?
Answer:
No ! the money spent on advertisement is not social waste, but it is an investment. Advertising plays a beneficial role for boosting up the sale, profit and reputation of the modern business. It provides benefits not only traders but to the customers and society also, which have been discussed below:

1. Increase Sales : The mein objective of advertisement is to increase sales production on a large scale, makes it necessary to sell on a large scale. Advertisement helps to create a wide base to facilities sales on large scale.
2. Steady demand : In the absence of personal touch between the buyers and the sellers, it is necessary to keep customers constantly aware and informed of the product so that there could be a steady demand for the products. This continuous information is provided through advertisement.
3. Helps in making decesion : Customers get the required information types of product available in the market to satisfy their demand their relative advantage or disadvantages, price and utility, etc. On the basis of this information a customer finds it easy to arrive at any decision. Selection becomes essay for him.
4. Educating customers : Advertisement educate people about various products and their diverse uses. It tells consumers about better ways of living there by increasing living standards.
5. Provide Employment : Advertisement is a source of employment for many persons. Making advertising copies dicussion with sponsors, printing the Advertisement etc require the services of many persons.
6. Higher standard of living : It helps to raise the standard of living by educating people, by providing them more job opportunities and facilitating in production on a large scale.

Question 30.
What do you mean by staffing is it a part of Human Resource Management ? Clarify.
Answer:
Staffing : ‘Staffing’is the term used when recruitment and selection, training and development, compensation and relesstion, etc. functions are performed for appointing and retaining managers. According to koontz, O’ Donnell and Weihrich “Staffing is the executive function which involves the recruitment, selection, compensating, training, promotions and retirement of subordinate managers.”

Yes ! It is a part of human resource management. Human resource management is a broad concept. “HRM is the art of processing, developing and maintaining suitable persons to acheive the goals of an organisation in on effective way. It is the way of optimising human competence at the work place. So that the goals of an organisation are accomplished effectively.” According to Ivancevich and Glueck, “HRM is concerned with the most effective use of people to acheive organisational and individuals goals. It is a way of managing people at work, so that they give their best to the organisation.”

Question 31.
“Co-ordination is the essence of management” Explain this statement.
Answer:
Co-ordination is the essence of management : Co-ordination is required at every step of management. It exist with each function of management planning presupposes application of the princeiples of Co-ordination for achieving objective of the fullness, managers have to ensure proper Co¬ordination among various persons and departments.

While establishing the organisational structure Co – ordination among varions positions must be given due consideration. The absence of Co-ordination weakens the effect of authority, responsibility relationship in the organisational structure. Like planning and organizing

Co-ordination has a relevance to other functions of management also. The importance of directing components, viz., communication leadership motivation and supervision increase if the Co – ordination principles have been interwoven with them. Similarly, Co-ordination enhances the importance of staffing & controlling.

Question 32.
Why is delegation necessary for an effective organisation.
Answer:
Delegation of authority is an important function of organisation, it helps in improving the managerial effectiveness. It is essential for effective organisation due to following reasons :

1. Relief to overburdened managers : As the business expand, seniors may become too heaving occupied. They may need the services of someone who can share their burden. They by the remedy by adopting the technique of delegation.
2. Improving in the quality & Quantity of work : When a single person has to do locuminous work the does it at the cost of its quality and quantity. He can take care of both if he shares it with someone. Delegation provides an opportunity to seniors for sharing their work with subordinates.
3. Sources of Enhancing job satisfaction : Delegation provides opportunities of job enlargement and job enrichment to sub-ordinates get more job satisfaction when they get additional challenging assignments.
4. Quick Decision making : Delegation also implies that delegatees will get the authority of decesions making in prescribed field. Since delegates get limited take through delegation they are able to take decesion quickly.
5. Facilitation of organisational Growth : The delegates get an exposure of doing higher level jobs. When organisation expands, the delegatees may he asked to take up the higher level positions resulting due to the expansion of the organisation.
6. Effective Co-ordination : Delegation stream lines the co-ordination and make it more effective.

Question 33.
Define Financial Management and discuss its objectives.
Answer:
Financial Management: If is the process of decision making and implementing it in all respects for the inflows and outflows of funds.
According to weston & Brighan, Financial management is an area of financial decision making, harmonising individuals motive and enterprise goals.
Objective of Financial Management :

(i) Profit Maximisation : Finance manager tries to augment the earning of profit. This may be done by procuring the optimum amount of finance by creating minimum liability on the company and by utilising the finance in the best possible way.

(ii) Wealth Maximisation : Along with the objective of profit maximisation, importance to wealth maximisation should also be attached. Both the objective should be considered side-by-side. In fact, wealth maximisation is increasingly being accepted as the goal of finance function.

Wealth of the company = No. of share X market price pershare
Wealth maximisation is a better goal of finance function since it represents the long term interest of shareholders.

Bihar Board 12th Biology Model Papers

Bihar Board 12th Biology Model Question Paper 1 in English Medium

Time : 3 Hours 15 Min
Total Marks : 70

Instructions for the candidates:

1. Candidates are required to give answers in their own words as far as practicable.
2. Figures in the right-hand margin indicate full marks.
3. While answering the questions, the candidate should adhere to the word limit as for as practicable.
4. 15 Minutes of extra time has been allotted for the candidates to read the questions carefully.
5. This question paper is divided into two sections: Section – A and Section – B
6. In Section – A, there are 35 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with blue/black ball pen against the correct option on OMR Sheet provided to you. Do not use Whitener/Liquid/ Blade/Nail on OMR Sheet otherwise result will be treated as invalid.
7. In Section – B, there are Non-objective type questions. There are 18 Short answer type questions, out of which any 10 questions are to be answered. Each question carries 2 marks. Apart from this, there are 6 long answer type questions, out of which any 3 of them are to be answered. Each question carries 5 marks
8. Use of any electronic device is prohibited.

Objective Type Questions

Question No. 1 to 35 have four options provided out of which only one is correct. You have to mark your selected option on the OMR-Sheet. Each question carries 1 (one) mark. (1 × 35 = 35)

Question 1.
Scientific/Botanical name of Pear is
(a) Pyrus communis
(b) Pisum sativum
(c) Pyrus malus
(d) None of them
Answer:
(a) Pyrus communis

Question 2.
Reproduction by Budding occurs in which of the followings:
(a) Yeast
(b) Hydra
(c) Both A and B
(d) Amoeba
Answer:
(c) Both A and B

Question 3.
Vegetative propagation is carried out by means of Rhizome in
(a) Potato
(b) Ginger
(c) Turmeric
(d) B and C both
Answer:
(d) B and C both

Question 4.
Which among the following is an example of Bulb?
(a) Ginger
(b) Potato
(c) Onion
(d) Radish
Answer:
(c) Onion

Question 5.
Which type of Endosperm is found in Angiosperms?
(a) Haploid
(b) Diploid
(c) Triploid
(d) None of these
Answer:
(c) Triploid

Question 6.
In which of the followings Pollinia are found?
(a) Calotropis
(b) Pea
(c) Gram
(d) Grass
Answer:
(a) Calotropis

Question 7.
Which among the following is an example of Parthenocarpic fruit?
(a) Apple
(b) Pear
(c) Banana
(d) None of these
Answer:
(c) Banana

Question 8.
Mammary glands are modified
(a) Endocrine gland
(b) Lachrymal gland
(c) Sweat gland
(d) None of these
Answer:
(c) Sweat gland

Question 9.
Hoemochorial Placenta is found in which among the followings?
(a) Horse
(b) Human being
(c) Rabbit
(d) Dog
Answer:
(b) Human being

Question 10.
The test which is used for study of genetic disorders in a Foetus is called as
(a) Angiogram
(b) Laparoscopy
(c) Amniocentesis
(d) Clotting test
Answer:
(c) Amniocentesis

Question 11.
Cuscuta is
(a) Epiphytes
(b) Root Parasite
(c) Total stem parasite
(d) Both B and C
Answer:
(c) Total stem parasite

Question 12.
Which among the following is an example of Hydrophytes?
(a) Lotus
(b) Hydrilla
(c) Trapa
(d) All of these
Answer:
(d) All of these

Question 13.
Mutations can be induced by
(a) Gamma radiation
(b) Infra-red radiation
(c) Ethylene
(d) IAA
Answer:
(a) Gamma radiation

Question 14.
How many genes are responsible for ABO system of blood group in humans?
(a) one
(b) two
(c) three
(d) four
Answer:
(c) three

Question 15.
What is the distance between consecutive two nucleotides of B-DNA?
(a) 2.7 A
(b) 3.4 A
(c) 3.32 A
(d) 3.7A
Answer:
(b) 3.4 A

Question 16.
Which among the following is termination codon?
(a) AUG
(b) GUG
(c) UAA
(d) AAA.
Answer:
(c) UAA

Question 17.
The characteristic feature of DNA double helix is
(a) Complementary & anti-parallel
(b) Always circular
(c) Parallel
(d) All of these
Answer:
(a) Complementary & anti-parallel

Question 18.
Which among the following is vestigial organs in Man?
(a) Nictitating membrane
(b) Coccyx
(c) Both A and B
(d) Pelvic
Answer:
(c) Both A and B

Question 19.
The bird Archaeopteryx was found in which period?
(a) Triassic
(b) Jurassic
(c) Cretaceous
(d) None of these
Answer:
(a) Triassic

Question 20.
The study of fossils is called as
(a) Entomology
(b) Paleontology
(c) Analogy
(d) Homology
Answer:
(b) Paleontology

Question 21.
Which among the following sequence defines Ribonucleotide?
(a) Ribose sugar + Nitrogenous base
(b) Ribose sugar + Protein
(c) Ribose sugar + Phosphoric acid
(d) Ribonucleoside + Phosphate group
Answer:
(d) Ribonucleoside + Phosphate group

Question 22.
Name the organelle which helps in translation.
(a) Lysosome
(b) Ribosome
(c) Spliciosome
(d) Exone
Answer:
(b) Ribosome

Question 23.
Humoral immunity is related to which among the followings?
(a) A-cells
(b) B-cells
(c) T-cells
(d) K-cells
Answer:
(b) B-cells

Question 24.
Which among the following is Causative organism of Typhoid disease:
(a) Bacillus anthracis
(b) Plasmodium vivax
(c) Salmonella typhi
(d) None of these
Answer:
(c) Salmonella typhi

Question 25.
What is common to Earthworm, Mushroom, Dung beetle and Soil mites? They all are
(a) Herbivores
(b) Carnivores
(c) Omnivores
(d) Detritivores
Answer:
(d) Detritivores

Question 26.
Gir forest is famous for
(a) Giraffe
(b) Cheetah
(c) Deer
(d) Lion
Answer:
(b) Cheetah

Question 27.
What are the types of food chains in an Ecosystem?
(a) Grazing
(b) Detritus
(c) Both A and B
(d) None of these
Answer:
(c) Both A and B

Question 28.
Which among the following animals become extinct?
(a) White peacock
(b) Dodo
(c) Deer
(d) Tiger
Answer:
(b) Dodo

Question 29.
Which among the following is Xerophytic plant?
(a) Trapa
(b) Casuarina
(c) Opuntia
(d) Both b and c
Answer:
(c) Opuntia

Question 30.
An example of a natural gene cloning vector is-
(a) Circular plasmid
(b) Linear plasmid
(c) Ti-plasmid
(d) Virion
Answer:
(c) Ti-plasmid

Question 31.
Acid rain occurs due to
(a) CO and CO₂
(b) NO₂ and SO₂
(c) CO₂ and NO₂
(d) N₂ and NO₂
Answer:
(b) NO₂ and SO₂

Question 32.
Sharbati Sonora and Kalyan Sona are improved varieties of which among the followings?
(a) Rice
(b) Wheat
(c) Maize
(d) Pulses
Answer:
(b) Wheat

Question 33.
Which bacteria transform milk into curd?
(a) Clostridium
(b) Micrococcus
(c) Lactobacillus
(d) Streptococcus
Answer:
(c) Lactobacillus

Question 34.
Somatic embryogenesis can be done by
(a) Cell culture
(b) Tissue culture
(c) Protoplast culture
(d) Both B and C
Answer:
(b) Tissue culture

Question 35.
RNAi is a method used to control
(a) Ball worms
(b) Nematodes
(c) Bacteria
(d) Fungi
Answer:
(b) Nematodes

Non-Objective Type Questions

Short Answer Type Questions

In this section, there are 18 short answer type question (each carries 2 marks) out of which answers any ten (10) questions. (10 x 2 = 20)

Question 1.
What do you mean by Global Warming? Explain.
Answer:
If there is excess increase in concentration of greenhouse gases in the atmosphere, then it would retain more and more of the infra-red radiation resulting in an enhanced greenhouse effect. Consequently, there will be increase in the global mean temperature which is referred to as Global Warming. It will cause melting of polar ice cap and glaciers. It also causes rise in sea level.

Question 2.
Describe the types of Biodiversity.
Answer:
Following are the types of Biodiversity :

1. Genetic diversity.
2. Species diversity
3. Ecological diversity.

Question 3.
Write an account of four benefits of transgenic animals for human welfare.
Answer:
Following are the benefits of transgenic animals :

1. Transgenic animals are routinely used in the laboratory as models in biomedical research.
2. Transgenic cow produces insulin in milk.
3. Transgenic sheep produces more wool.
4. Transgenic animals can be specifically designed to allow the study of how genes are regulated and how they affect the normal functioning of the body.

Question 4.
What is Binary fission ? Give suitable examples. Show it with the help of diagram.
Answer:
Binary fission reproduction takes place in Amoeba. Amoeba withdraws its pseudopodia and the nucleus divides by mitosis. A constriction appears in the middle and the amoeba gets divided into two daughter amoeba.Binary fission takeks place under favourable conditions.

Question 5.
What are Initiation codons ? Name them.
Answer:
AUG is in itiation codon. AUG stands for methionine, polypeptide chain begins with methionine

Question 6.
What do you understand by Tissue Culture? Illustrate its any two advantages.
Answer:
Plant tissue culture is the maintenance and growth of plant cells, tissues and organs on a suitable culture medium in vitor (in a container e.g., test tube).
Advantages of tissue culture: (i) Tissue culture helps to produce more copies of same plant with desired characters.
(i) It produces some clonal variations.

Question 7.
Draw the sketches of a Zoospore and a Conidium.
Answer:

Question 8.
Mention advantages of self pollination.
Answer:
Advantages :

1. It provides greater chances for pollination of flower.
2. It is economical and pollen grains are not to be produced in enormous quantities to ensure pollination.
3. There is no necessity of flower to be showy and of bright colour to attract pollinators.
4. It preserves the desired and parental charracters of plants.

Question 9.
What are Communicable diseases in human beings ? Describe with suitable examples.
Answer:
Such diseases which arise directly or indirectly through infection of one to another person.
Ex: Tuberculosis, Cholera, Malaria, AIDS, etc.

Question 10.
Write about poultry farm management in brief.
Answer:
It deals with the management and rearing of flows (chickens) ducks, turkeys and pleasants for the production of eggs and meats.
Steps of proper management of poultry farm :

1. Selection of disease free and suitable breeds.
2. Provision of moderate climatic conditions during summer and winter.
3. Provision of nutritions used and water.
4. Providing comfortable, well ventilated, dry and well illuminated poultry house.
5. Regular check up of poultry birds for diagnosis and treatment.

Question 11.
Write expanded form of the following:
(A) G.M.O.
(B) S.T.D.
(C) A.M.P.
(D) V.N.T.R.
Answer:
(A) G.M.O: Genetically Modified Organism.
(B) S.T.D: Sexually Transmitted disease.
(C) A.M.P.: Adenosine Mono Phosphate.
(D) V.N.T.R.: Variable Number Tandem Repeat.

Question 12.
Distinguish between Missing link and Connecting link.
Answer:
Missing link: It is a hypothetical extinct creature halfway in the evolutionary line between modern human beings and their anthropoid progenitors. Connecting link : Connecting link is an organism having characteristics of two different group of organisms, Ex : Peripatus is a connecting link between Annelida and Arthropoda.

Question 13.
Differentiate between :
(A) Ovipary and Vivipary
(B) Oestrius cycle and Menstrual cycle.
Answer:
(A) Ovipary: These are egg laying organisms, Ex: Fish, Frog etc.
Vivipary : Here development of embryo inside the body of parent takes place, leading to live birth of young ones. Ex. Man, Cow , etc.
(B) Oestrius Cycle and Menstrual Cycle : The females of placental mammals exhibits cyclical changes in the activities of ovaries and accessory ducts as well as hormones during the reproductive phase. However in non – primate mammals like cows, sheep, rats, deers, tiger etc, such cyclical changes occurs during reproduction are called oestrius cycle whereas in primates, e.g. monkeys, apes, & humans it is called menstrual cycle.

Question 14.
Write the scientific name of causal organism of Malaria and Elephantiasis diseasse of human being.
Answer:
(i) Malaria : Plasmodium vivax.
(ii) Elephantiasis : Wuchereria bancrafti

Question 15.
What do you understand by noise pollution. Describe its various causes.
Answer:
Noise pollution is the propagation of noise with harmful impact on the activity of human life.
Sources : Washing Machine, Cooler, Vacuum Cleaner etc.

Question 16.
Mention any two applications of GelElectrophoresis in Biotechnology.
Answer:
Applications :
(i) DNA can be separated by Gel electrophoreny.
(ii) Electrophoeny is useful in both the creation and production of vaccines.

Question 17.
Match column A with B:
Answer:

Question 18.
Show diagrammatic representation of clover leaf model of t-RNA molecule and name the four arms.
Answer:

Long Answer Type Questions

There are 6 long answers type question (each carrying 05 marks) out of which answers any three questions. (5 x 3 = 15)

Question 19.
What do you understand by Bio-fertilizer? What are the benefits soil gets from them? Name any two such bio-fertilizers.
Answer:
Bio-fertilisers are organisms that enrich the nutrient quality of the soil. The main sources of bio-fertilisers are microbes (eg. Bacteria, Fungi and Cyano-bacteria). The nodules on the roots of legunminous plants formed by the symbiotic association of Rhizobium, fix atmospheric nitrogen into organic forms, which is used by the plants as nutrient. Other bacteria can fix atmospheric nitrogen while free-living in the soil (eg. Azospirillum and Azotobacter), thus enriching the nitrogen content of the soil.

Fungi are also known to form symbiotic associations with plants (mycohiza). The fungi symbiont in these association absorbs phosphorus from soil and passes it to the plants. Plants having such associations show other benefits also, such as resistance to root-borne pathogens, tolerance to salinity and drought and an overall increase in plant growth and development.

Cyano-bacteria are autotrophic microbes which can fix atmospheric nitrogen, eg. Anabaena, Nostoc, Oscillatoria, etc. In paddy fields, Cyano-batetiar serve as an important bio-fertiliser. Blue green algae also add organic matter to the soil and increases its fertility. Currently, in our country, a number of fertilisers are available commercially in the market and farmers use these regularly in their fields to replenish soil nutrients and to reduce dependence on chemical fertilisers.

Question 20.
Show food-chain in a fresh water pond and illustrate it with the help of diagram.
Answer:

(saprophytic bacteria and fungi)

Question 21.
What do you understand by Mutation? What are their main types and mention its significance in brief.
Answer:
Mutation is defined as change in gene which is heritable.
The abrupt changes may take place in chromosomes, then it is called chromosomal mutation.

Types of Mutation:

1. Somatic mutation: It occurs in somatic cells and it is non-heritable.
2. Germinal mutation: It is found in reproductive cells and is heritable.
3. Spontaneous mutation: Mutation occuring in nature is called spontaneous mutation.
4. Induced mutation: When mutation is produced by mutagenic chemicals or radiations.

Significance:
Role of Mutation in Evolution: Evolution is a slow and continuous process for evolution. The basic necessity is variation. The variation among plants and animals are brought about by mutation.

Question 22.
What do you mean by Cry-protein? It is obtained from which organism? Describe its various uses.
Answer:
Cry proteins are crystalline toxins which are encoded by cry genes. It is obtained by Bacillus touring – genesis bacteria. The bacterium contains these proteins in their inactive form. When the inactive toxin protein is ingested by the insect it gets activated by the alkaline pH of the gut.

Uses of Cry-protein :

1. It protects cotton plants from ball-worms.
2. Many transgenic crops are produced.

Question 23.
What do you mean by Foetal Membrane? Mention its types and explain it in brief.
Answer:
The Foetal membranes are membranes associated with the developing Foetus. The two chorio-amniotic membranes are the amnion and the Chorion which make the amniotic sac surrounds and protects the foetus. The other foetal membranes are the allantois and the secondary umbilical vesicle.

Types of Foetal Membrane :

1. Amnion: The Amnion is a transparent greyish membrane which lines the chorian. It comes to the foetal surface of the placenta and the umbilical cord.
2. Chorion: The chorion is a double-layered membrane formed by the trophoblast and the extraembryonic mesoderm which eventually give rise to foetal part of the placenta.

Question 24.
Write short notes on any two of the following :
(a) Fisheries
(b) Ribosome
(c) Infertility
(d) Red data book.
Answer:
(a) Fisheries: Fisheries is a kind of industry which is associated with fish and other aquatic animals (crab, prawn), and for thier production, processing and marketing management. The revolution in the field of increased production of fishes is called “Blue Revolution.’

(b) Ribosome: Ribosomes are found on the endoplasmic reticulum or scattered in the cytoplasm. These vary from 150-200 A° and are made of nucleo-protein. These are found as free granules or in groups. When these are found in granules, they are called poly-ribosome.

(c) Infertility: Inability to conceive or produce children even after two years of unprotected sexual co-habitation is called infertility.

(d) Red-data book: Red-data book is a catalogue of taxa that are facing the risk of extinction. Its main aim is to give information about the urgency and scale of conservation problem to the public and policymakers.

Bihar Board Class 11 Biology Solutions Chapter 21 तंत्रिकीय नियंत्रण एवं समन्वय Textbook Questions and Answers, Additional Important Questions, Notes.

BSEB Bihar Board Class 11 Biology Solutions Chapter 21 तंत्रिकीय नियंत्रण एवं समन्वय

Bihar Board Class 11 Biology तंत्रिकीय नियंत्रण एवं समन्वय Text Book Questions and Answers

प्रश्न 1.
निम्नलिखित संरचनाओं का संक्षेप में वर्णन कीजिए –
(अ) मस्तिष्क
(ब) नेत्र
(स) कर्ण।
उत्तर:
(अ) मानव मस्तिष्क की रचना (Structure of Human Brain):
मनुष्य में मस्तिष्क कपाल या ऊनियम (cranium) के भीतर सुरक्षित रहता है। मस्तिष्क तीन आवरणों से ढका रहता है जिन्हें मस्तिष्कावरण (meninges) कहते हैं। ये मस्तिष्कावरण है –

1. दृढ़तानिका (Duramater):
श्वेत तन्तुमय ऊतक की बनी होती है।

2. जालतानिका (Arachnoid mater):
यह मध्य की पर्त है।

चित्र – मानव मस्तिष्क की रचना – खड़ी काट में।

3. मृदुतानिका (Piamater):
यह सबसे भीतरी आवरण है, जो मस्तिष्क के सम्पर्क में रहता है। इस पर्त में रुधिर वाहिनियों का जाल बिछा रहता है। इन झिल्लियों के बीच एक तरल भरा रहता है जिसे सेरेब्रोस्पाइनल तरल (cerebrospinal fluid) कहते हैं। यह द्रव पोषण, श्वसन तथा उत्सर्जन में सहायक है। यह बाहरी आधातों से कोमल मस्तिष्क की सुरक्षा भी करता है।

मस्तिष्क को तीन भागों में बाँटा जा सकता है –

1. अग्रमस्तिष्क (Fore brain)
2. मध्य-मस्तिष्क (Mid brain)
3. पश्चमस्तिष्क (Hind brain)

1. अग्रमस्तिष्क या प्रोसेनसिफैलॉन (Fore brain or Prosencephalon):

अग्र मस्तिष्क के तीन भाग होते हैं –

1. घ्राण भाग
2. सेरेब्रम तथा
3. डाइएनसिफैलॉन।

(i) मनुष्य में घ्राण भाग अवशेषी होता है तथा अग्रमस्तिष्क का मुख्य भाग सेरिब्रम होता है।

(ii) प्रमस्तिष्क या सेरेब्रम (Cerebrum):
मस्तिष्क का लगभग 2/3 भाग प्रमस्तिष्क होता है। प्रमस्तिष्क दो पालियों में बँटा होता है जिन्हें प्रमस्तिष्क गोलार्द्ध (cerebral hemispheres) कहते हैं। दोनों प्रमस्तिष्क गोलार्द्ध तन्त्रिका तन्तुओं की एक पट्टी द्वारा जुड़े रहते हैं जिसे कॉर्पस कैलोसम (corpus callosum) कहते हैं। प्रमस्तिष्क में तन्त्रिका कोशिकाएँ इस प्रकार स्थित होती हैं कि इनके कोशिकाकाय बाहर की ओर स्थित होते हैं।

इस भाग को प्रमस्तिष्क वल्कुट (cerebral cortex) कहते हैं भीतर की ओर तन्त्रिका कोशिकाओं पर अक्षतन्तु (axon) स्थित होते हैं। यह भाग प्रमस्तिष्क मध्यांश (cerebral medulla) कहलाता है। बाहरी भाग धूसर (ग्रे) रंग का होता है। इसे धूसर द्रव्य (grey matter) कहते हैं। भीतरी भाग श्वेत-(सफेद) रंग का होता है। इसे श्वेत द्रव्य (white matter) कहते हैं।

प्रमस्तिष्क की पृष्ठ सतह में तन्त्रिका तन्तुओं की अत्यधिक संख्या होने के कारण यह सतह अत्यधिक मोटी व वलनों वाली (folded) हो जाती है। इस सतह को नियोपैलियम (neopallium) कहते हैं। नियोपैलियम में उभरे हुए भागों को उभार या गायराई (gyri) तथा बीच के दबे भाग को खाँच या सल्काई (sulci) कहते हैं।

तीन गहरी दरारें प्रत्येक प्रमस्तिष्क गोलार्द्ध को चार मुख्य पालियों में बाँट देती हैं। इन्हें फ्रन्टल पालि (frontal lobe), पैराइटल पालि (parietal lobe), टैम्पोरल पालि (temporal lobe) तथा ऑक्सीपीटल पालि (occipital lobe) कहते हैं। प्रमस्तिष्क की गुहाओं को पार्श्व मस्तिष्क गुहा या पैरासील (paracoel or lateral ventricles) कहते हैं।

(iii) अग्रमस्तिष्क ‘पश्च या डाइएनसिफैलॉन (Diencephalon):
यह अग्रमस्तिष्क का पिछला भाग है। इसका पृष्ठ भाग पतला होता है तथा अधर भाग मोटा होता है जिसे हाइपोथैलैमस (hypothalamus) कहते हैं। हाइपोथैलेमस की अधर सतह पर इन्फन्डीबुलम (infundibulum) से जुड़ी पीयूष ग्रन्थि होती है।

डाइएनसिफैलॉन की पृष्ठ सतह पर पीनियल काय (pineal body) तथा अग्र रक्त जालक, (anterior choroid plexus) पाया जाता है। डाइएनसिफैलॉन की गुहा तृतीय निलय (third ventricle) या डायोसील (diocoel) होती है, यह पार्श्व गुहाओं से मोनरो के छिद्र (foramen of Monaro) द्वारा जुड़ी रहती है।

II. मध्यमस्तिष्क या मीसेनसिफैलॉन (Mid Brain or Mesencephalon):
यह भाग स्तनियों में बहुत अधिक विकसित नहीं होता है। इसका पृष्ठ भाग चार दृक् पालियों के रूप में होता है, जिन्हें कॉर्पोरा क्याड्रिजेमिना (corpora quadrigemina) कहते हैं। मध्यमस्तिष्क के पार्श्व व अधर भाग में तन्त्रिका ऊतक की पट्टियाँ होती हैं जिन्हें क्रूरा सेरेब्राई (crura cerebri) कहते हैं। ये पश्चमस्तिष्क को अग्रमस्तिष्क से जोड़ने का कार्य करती हैं। यहाँ दृक् तन्त्रिकाएँ एक-दूसरे को क्रॉस करके, ऑप्टिक कियाज्मा (optic chiasma) बनाती है। मध्यमस्तिष्क की सँकरी गुहा को आइटर (iter) कहते हैं, जो तृतीय निलय को चतुर्थ निलय (fourth ventricle) से जोड़ती हैं।

III. पश्चमस्तिष्क या रॉम्बेनसिफैलॉन (Hind brain or Rhombencephalon):
यह मस्तिष्क का पश्च भाग है। इसे मस्तिष्क वृन्त (brain stalk) भी कहते हैं। पश्च मस्तिष्क के दो भाग होते हैं –

(i) अनुमस्तिष्क (cerebellum)
(ii) मस्तिष्क पुच्छ या मेडुला ऑब्लांगेटा (medulla oblongata)।

(i) अनुमस्तिष्क (Cerebellum):
यह प्रमस्तिष्क के पिछले भाग से सटा रहता है। अनुमस्तिष्क दो पार्श्व गोला? (lateral hemispheres) का बना होता है। अनुमस्तिष्क में बाहरी धूसर द्रव्य तथा आन्तरिक श्वेत द्रव्य होता है। श्वेत द्रव्य में स्थान-स्थान पर धूसर. द्रव्य प्रवेश करके वृक्ष की शाखाओं जैसी रचना बनाता है। इसे प्राणवृक्ष या आरबर विटी (arbor vitae) कहते हैं। अनुमस्तिष्क में गुहा अनुपस्थित होती है। अनुमस्तिष्क के अधर भाग में श्वेत द्रव्य की एक पट्टी होती है जिसे पोंस वेरोली (pons varolli) कहते हैं।

(ii) मस्तिष्क पुच्छ या मेडुला ऑब्लांगेटा (Medulla Oblongata):
यह मस्तिष्क का सबसे पिछला भाग है जो आगे मेरुरज्जु के रूप में कपाल गुहा से बाहर निकलता है। मेडुला की पृष्ठ भित्ति पर पश्च रक्त जालक (posterior choroid plexus) स्थित होता है। मेडुला की गुहा को चतुर्थ निलय या मेटासील (fourth ventricle or metacoel) कहते हैं।

(ब) नेत्र की संरचना (Structure of Eye):
मनुष्य में एक जोड़ी नेत्र चेहरे पर सामने की ओर नेत्र कपाल के नेत्र कोटर (eye orbit) में स्थित होते हैं। प्रत्येक नेत्र एक तरल से भरे गोलक के रूप में होता है। नेत्र गोलक का 4/5 भाग नेत्र कोटर में और लंगभग 1/5 भाग नेत्र कोटर के बाहर स्थित होता है। नेत्र गोलक की भित्ति तीन स्तरों से बनी होती है। सबसे बाहरी दृढ़पटल (sclera), मध्य रक्तकपटल (choroid) तथा भीतरी दृष्टिपटल (retina) है।

1. दृढ़पटल या स्क्ले रोटिक (Sclera or Sclerotic):
यह तन्तुमय संयोजी ऊतक का बना सबसे बाहरी स्तर है। इसका वह भाग जो नेत्र कोटर से बाहर होता है, पारदर्शी होता है तथा इसे कॉर्निया (cornea) कहते हैं।

चित्र – मानव नेत्र की रचना-खड़ी काट में।

2. रक्तकपटल या कोरॉइड (Choroid):
यह नेत्र गोलक की भित्ति का मध्य स्तर है। रक्तकपटल संयोजी ऊतक का बना स्तर है जिसमें रुधिर केशिकाओं का घना जाल होता है। रक्तकपटल में रंगायुक्त कोशिकाएँ होती हैं, जिस कारण नेत्र का रंग काला, भूरा, सुनहरा या नीला दिखाई देता है। रक्तकपटल का वह भाग जो कॉर्निया के नीचे होता है, थोड़ी पीछे हटकर एक पेशीय पर्दे जैसी रचना (diaphragm like) बनाता है जिसे आइरिस या उपतारा (iris) कहते हैं।

आइरिस अरीय (radial) तथा वर्तुल पेशियों (circular muscles) का बना होता है। आइरिस के मध्य में एक गोल छिद्र होता है। जिसे तारा या पुतली (pupil) कहते हैं। अरीय पेशियाँ तारे के छिद्र को बड़ा करती है; अतः इन्हें प्रसारी पेशियाँ (dilatory muscles) कहते हैं। वर्तुल पेशियाँ तारे के छिद्र को छोटा या संकुचित करती हैं; अतः इन्हें स्फिक्टर (अवरोधिनी) पेशियाँ (sphincter muscles) कहते हैं। तारा नेत्र में प्रवेश करने वाले प्रकाश की मात्रा को नियन्त्रित करता है।

चित्र – आइरिस व तारे की रचना

आइरिस के आधार पर रक्तपटल अत्यधिक मोटा व पेशीयुक्त होकर सीलियरी काय (ciliary body) बनाता है।

3. दृष्टिपटल या रेटिना (Retina):
यह नेत्र भित्ति का सबसे भीतरी प्रकाश संवेदी (light sensitive) स्तर है। रेटिना में रक्तकपटल की ओर एक पतला वर्णक स्तर (pigmented layer) तथा भीतर की ओर तन्त्रिका संवेदी स्तर होता है।

तन्त्रिका संवेदी. स्तर (neurosensory layer) प्रकाश के लिए संवेदनशील होता है। यह निम्नलिखित प्रकार का पर्तों से बना होता है –

(i) दृष्टि शलाकाओं एवं शंकुओं का स्तर (Layer of Rods and Cones):
शलाकाओं में दृष्टि पर्पल (visual purple) वर्णक रोडोप्सिन (Rhodopsin) तथा शंकुओं में दृष्टि वॉयलेट (visual violet) वर्णक आयोडोप्सिन (iodopsin) पाए जाते हैं। शलाकाएँ प्रकाश व अन्धकार में भेद करती हैं, जबकि शंकु रंगों का ज्ञान कराते हैं।

(ii) ध्रुवीय न्यूरॉन का स्तर (Layer of Bipolar Neurons):
इसकी तन्त्रिका कोशिकाएँ दृष्टि शलाकाओं एवं शंकुओं के स्तर को गुच्छकीयं कोशिकाओं के स्तर से जोड़ती हैं।

(iii) गुच्छकीय कोशिकाओं का स्तर (Layer of Ganglionic Cells):
इसकी कोशिकाओं के एक्सॉन तन्तु मिलकर दृक् तन्त्रिका (optic nerve) बनाते हैं। दृक् तन्त्रिका जिस स्थान से रेटिना से निकलती है, उसे अन्ध बिन्दु (blind spot) कहते हैं, इस स्थान पर प्रतिबिम्ब का निर्माण नहीं होता है।

नेत्र की मध्य अनुलम्ब् अक्ष (optical axis) पर स्थित रेटिना के मध्य भाग को मध्य क्षेत्र (area centralis) कहते हैं। इस भाग को पीत बिन्दु (yellow spot) या मैकुला ल्यूटिया (macula lutea) भी कहते हैं। यहाँ उपस्थित एक छोटे से गड्ढे को फोविया सेन्ट्रेलिस (fovea centralis) कहते हैं। इस स्थान पर सबसे स्पष्ट प्रतिबिम्ब बनता है।

लेन्स (lens):
यह उभयोत्तल (biconvex), पारदर्शी, रंगहीन व लचीला होता है। यह आइरिस के ठीक पीछे स्थित होता है। लेन्स साधक स्नायु (suspensory ligament) द्वारा सीलियरी काय (ciliary body) से जुड़ा होता है। तेजो वेश्म या ऐक्वस वेश्म (aqueous chamber) कॉर्निया तथा लेन्स के बीच का स्थान होता है।

इसमें जलीय तरल तेजोजल या ऐक्वस ह्यमर (aqueous humor) भरा रहता काचाभ वेश्म या विट्रियस वेश्म (vitreous chamber) रेटिना व लेन्स के बीच का स्थान है। इसमें जैली सदृश काचाभ जल यो विट्रियस हमर (vitreous humor) भरा रहता है। जलीय तेजोजल तथा जैली सदृश काचाभ जल सीलियरी काय द्वारा स्रावित होते हैं। ये नेत्र की गुहा में निश्चित दबाव बनाए रखते हैं जिससे दृष्टिपटल व अन्य नेत्रपटल यथास्थान बने रहें।

पलक (Eye Lids):
नेत्र कोटर के ऊपरी व निचले भागों में त्वचा के पेशीयुक्त भंज (folds) पलकों का निर्माण करते हैं। दोनों पलके सचल होती हैं तथा नेत्र गोलक के खुले भाग को ढक सकती हैं। पलकों की भीतरी उपचर्म (epidermis) पारदर्शी होकर कॉर्निया के साथ समेकित हो जाती है। इसे नेत्र श्लेष्मा या कन्जंक्टिवा (conjunctiva) कहते हैं। पलकों पर बरौनियाँ (eye lashes) पाई जाती है। खरगोश तथा अन्य स्तनियों में एक तीसरी पलक होती है, जिसे निमेषक पटल (nictitating membrane) कहते हैं। यह पलक नेत्रों की सुरक्षा का कार्य करती है। मनुष्य में यह अवशेषी होती है।

अश्रु ग्रन्थियाँ (Lacrimal Glands or Tear Glands):
प्रत्येक नेत्र के बाहरी ऊपरी कोने पर तीन अश्रु ग्रन्थियाँ स्थित ‘होती हैं। इनका स्राव कॉर्निया व कन्जंक्टिवा को नम तथा स्वच्छ बनाए रखता है। नेत्र के भीतरी कोण पर एक अश्रु नलिका (lachrymal duct) होती है जो फालतू स्राव को नासा वेश्म में पहुँचा देती है। जन्म के चार माह पश्चात् मानव शिशु में अश्रु ग्रन्थियाँ सक्रिय होती हैं।

मीबोमियन ग्रन्थियाँ (Meibomian glands):
ये पलकों में स्थित होती हैं तथा एक तैलीय पदार्थ का स्रावण करती हैं। यह तैलीय पदार्थ कॉर्निया पर फैलकर अश्रु ग्रन्थियों के स्रावण को पूरी कॉर्निया पर फैलाता है।

(स) कर्ण की संरचना (Structure of Ear):
कर्ण श्रवण तथा स्थैतिक सन्तुलन (hearing and equilibrium) का अंग है।
प्रत्येक कर्ण के तीन भाग होते हैं –

(i) बाह्य कर्ण
(ii) मध्य कर्ण तथा
(iii) अन्त:कर्ण।

(i) बाह्य कर्ण (External Ear):
मनुष्य में बाह्य कर्ण के दो भाग होते हैं – कर्ण पल्लव (pinna) तथा बाह्य कर्ण कुहर (external auditory canal) कर्ण पल्लव केवल स्तनियों में ही पाए जाते हैं। ये लचीली उपास्थि से बनी पंखेनुमा रचना है। कर्ण पल्लव ध्वनि तरंगों को कर्ण कुहर में भेजता है। बाह्य कर्ण कुहर एक अस्थिल नलिका है, जो मध्य कर्ण से जुड़ी रहती है। बाह्य कर्ण कुहर के अन्तिम सिरे पर एक पर्दे जैसी रचना कर्णपटह (tymapanic membrane) होती है।

(ii) मध्य कर्ण (Middle Ear):
यह करोटि की टिम्पैनिक बुल्ला (tympanic bulla) नामक अस्थि की गुहा में स्थित होता है। मध्य कर्ण कण्ठ कर्ण नलिका या यूस्टेकियन नलिका (eustachian tube) द्वारा ग्रसनी (pharynx) से जुड़ा रहता है।

मध्य कर्ण में तीन कर्ण अस्थिकाएँ(ear ossicles) होती है। इन्हें मैलियम, इन्कस तथा स्टैपीज (malleus, incus and stapes) कहते हैं। मैलियस कान के पर्दे से सटी रहती है तथा स्टैपीज अन्त:कर्ण की ओर अण्डाकार गवाक्ष या फेनेस्ट्रा ओवेलिस (fenestra ovalis) पर स्थित होती है।

चित्र – मनुष्य का कर्ण

ये तीनों कर्ण अस्थिकाएँ ध्वनि तरंगों को बाह्य कर्ण से अन्त: कर्ण तक पहुँचाने का कार्य करती हैं।

मध्य कर्ण दो छिद्रों द्वारा अन्तःकर्ण की गुहा से जुड़ा होता है, इन्हें अण्डाकार गवाक्ष या फेनेस्ट्रा ओवेलिस (fenestra ovalis) तथा वृत्ताकार गवाक्ष या फेनेस्ट्रा रोटन्डस (fenestra rotundus) कहते हैं। इन छिद्रों के ऊपर झिल्ली उपस्थित होती है।

(iii) अन्तःकर्ण (Internal Ear):
अन्त:कर्ण करोटि की टैम्पोरल अस्थि के भीतर स्थित होता है। अन्तःकर्ण एक अर्द्धपारदर्शक झिल्ली से बनी जटिल रचना होती है, जिसे कलागहन (membranous labyrinth) कहते हैं। कलागहन अस्थि के बने कोष में स्थित रहता है जिसे अस्थीय लेबिरिन्थ (bony labyrinth) कहते हैं। अस्थीय लेबिरिन्थ में परिलसीका (perilymph) भरा रहता है, जिसमें कलागहन तैरता रहता है। कलागहन के भीतर अन्तःलसीका (endolymph) भरा रहता है।

कलागहन के दो मुख्य भाग यूट्रिकुलस (utriculus) तथा सैक्यूलस (sacculus) होते हैं। दोनों भाग एक सँकरी सैक्यूलोयूट्रिकुलर नलिका (sacculo-utricular duct) द्वारा जुड़े रहते हैं। यूट्रिकुलस से तीन अर्द्धवृत्ताकार नलिकाएँ (semicircular canals) निकलकर यूट्रिकुलस में ही खुल जाती हैं।

अग्र तथा पश्च अर्द्धवृत्ताकार नलिकाएँ एकसाथ सहनलिका (crus commune) के रूप में निकलती हैं। अर्द्धवृत्ताकार नलिकाओं का अन्तिम भाग तुम्बिका (ampulla) के रूप में फूला होता है। सैक्यूलस से स्प्रिंग की तरह कुण्डलित कॉक्लियर नलिका (cochlear duct) निकलती है। इसमें 2 \(\frac{2}{3}\) कुण्डलन होते हैं।

प्रश्न 2.
निम्नलिखित की तुलना कीजिए –
(अ) केन्द्रीय तन्त्रिका तन्त्र और परिधीय तन्त्रिका तन्त्र
(ब) स्थिर विभवं और सक्रिय विभव
(स) कोरॉइड और रेटिना।
उत्तर:
(अ) केन्द्रीय तन्त्रिका तन्त्र तथा परिधीय तन्त्रिका तन्त्र में अन्तर (Difference between Central Nervous System and Peripheral Nervous System):

(ब) स्थिर विभव और सक्रिय विभव में अन्तर (Difference between Resting Potential and Action Potential):

(स) कोरॉइड और रेटिना में अन्तर (Difference between Choroid and Retina):

प्रश्न 3.
निम्नलिखित प्रक्रियाओं का वर्णन कीजिए –
(अ) तन्त्रिका तन्तु की झिल्ली का ध्रुवीकरण
(ब) तन्त्रिका तन्तु की झिल्ली का विधुवीकरण
(स) तन्त्रिका तन्तु के समांतर आवेगों का संचरण
(द) रासायनिक सिनैप्स द्वारा तन्त्रिका आवेगों का संवहन।
उत्तर:
(अ) तन्त्रिका तन्तु की झिल्ली का ध्रुवीकरण (Polarisation of the Membrane of a Nerve Fibre):
तन्त्रिका तन्तु के ऐक्सोप्लाज्म में Na⁺ की संख्या बहुत कम, परन्तु ऊतक तरल में लगभग 12 गुना अधिक होती है। ऐक्सोप्लाज्म में K⁺ की संख्या ऊतक तरल का अपेक्षा लगभग 30-35 गुना अधिक होती है।

विसरण अनुपात के अनुसार Na⁺ की ऊतक तरल से ऐक्सोप्लाज्म में और K⁺ के ऐक्सोप्लाज्म से ऊतक तरल में विसरित होने की प्रवृत्ति होती है। लेकिन तन्त्रिकाच्छद या न्यूरीलेमा (neurilemma) Na⁺ के लिए कम और K⁺ के लिए अधिक पारगम्य होती है।

विश्राम अवस्था में ऐक्सोप्लाज्म में ऋणात्मक आयनों और ऊतक तरल में धनात्मक आयनों की अधिकता रहती है। तन्त्रिकाच्छद या न्यूरीलेमा की बाह्य सतह पर धनात्मक आयनों और भीतरी सतह पर ऋणात्मक आयनों का जमाव रहता है। तन्त्रिकाच्छद की बाह्य सतह पर धनात्मक और भीतरी सतह पर 70 mV का ऋणात्मक आवेश रहता है।

इस स्थिति में तन्त्रिकाच्छद या न्यूरीलेमा विद्युतावेशी या ध्रुवण अवस्था (polarised state) में बनी रहती है। तन्त्रिकाच्छद (neurilemma) के इधर-उधर विद्युतावेशी अन्तर (electric charge difference) के कारण न्यूरीलेमा में बहुत-सी विभव ऊर्जा संचित रहती है। इसी ऊर्जा को विश्राम कला विभव कहते हैं। प्रेरणा संचरण में इसी ऊर्जा का उपयोग होता है।

चित्र – विश्रामकला विभव, इसकी स्थापना तथा अनुरक्षण।

(ब) तन्त्रिका तन्तु की झिल्ली का विध्रुवीकरण (Depolarisation of the Membrane of Nerve Fibre):
जब एक तन्त्रिका तन्तु की ऐशहोल्ड उद्दीपन (threshold stimulus) दिया जाता है तो न्यूरीलेमा (neurilemma) की पारगम्यता बदल जाती है। यह Na⁺ के लिए अधिक पारगम्य हो जाती है और K⁺ के लिए अपारगम्य हो जाती है। इसके फलस्वरूप तन्त्रिका तन्तु विश्राम कला विभव की ऊर्जा का प्रेरणा संचरण के लिए उपयोग करने में सक्षम होते हैं।

तन्त्रिका तन्तु को उद्दीपित करने पर इसके विश्राम कला विभव की ऊर्जा एक विद्युत प्रेरणा के रूप में, तन्तु के क्रियात्मक कला विभव में बदल जाती है। यह विद्युत प्रेरणा तन्त्रिकीय प्रेरणा होती है। Na⁺ ऐक्सीप्लाज्म में तेजी से प्रवेश करने लगते हैं, इसके फलस्वरूप तन्त्रिका तन्तु का विध्रुवीकरण होने लगता है। विध्रुवीकरण के फलस्वरूप न्यूरीलेमा की भीतरी सतह पर धनात्मक और बाह्य सतह पर ऋणात्मक विद्युत आवेश स्थापित हो जाता है। यह स्थिति विश्राम अवस्था के विपरीत होती है।

(स) तन्त्रिका तन्तु के समान्तर आवेगों का संचरण (Conduction of Nerve Impulse along a Nerve Fibre):
तन्त्रिकाच्छद (न्यूरीलेमा) के किसी स्थान पर तन्त्रिका आवेग की उत्पत्ति होती है तो उत्पत्ति स्थल ‘A’ पर तन्त्रिकाच्छद Na⁺ के लिए अधिक पारगम्य हो जाती है, जिसके फलस्वरूप Na⁺ तीव्रगति से अन्दर आने लगते हैं तो न्यूरीलेमा की भीतरी सतह पर धनात्मक और बाह्य सतह पर ऋणात्मक आवेश स्थापित हो जाता है। आवेग स्थल पर विध्रुवीकरण हो जाने को क्रियात्मक विभव कहते हैं। क्रियात्मक विभव तन्त्रिकीय प्रेरणा के रूप में स्थापित हो जाता है।

तन्त्रिकाच्छद से कुछ आगे ‘B’ स्थल पर झिल्ली की बाहरी सतह पर धनात्मक और भीतरी सतह पर ऋणात्मक आवेश होता है। परिणामस्वरूप, तन्त्रिका आवेग ‘A’ स्थल से ‘B’ स्थल की ओर आवेग का संचरण होता है। यह प्रक्रम सम्पूर्ण एक्सॉन में दोहराया जाता है। इसके प्रत्येक बिन्दु पर उद्दीपन को सम्पोषित किया जाता रहता है। उद्दीपन किसी भी स्थान पर अत्यन्त कम समय तक (0.001 से 0.005 सेकण्ड) तक ही रहता है।

जैसे-ही भीतरी सतह पर धनात्मक विद्युत आवेश + 35mv होता है, तन्त्रिकाच्छद की पारगम्यता प्रभावित होती है। यह पुन: Na⁺ के लिए अपारगम्य और K⁺ के लिए अत्यधिक पारगम्य हो जाती है। K⁺ तेजी से ऐक्सोप्लाज्म में ऊतक तरल से जाने लगते हैं। सोडियम-पोटैशियम पम्प पुन: सक्रिय हो जाता है जिससे तन्त्रिका तन्तु विश्राम विभव में आ जाता है। अब यह अन्य उद्दीपन के संचरण हेतु फिर तैयार हो जाता है।

(द) रासायनिक सिनैप्स द्वारा तन्त्रिका आवेगों का संवहन (Transmission of Nerve Impulse across a Chemical Synapse):
अक्षतन्तु (axon) के अन्तिम छोर पर स्थित अन्त्य बटन (terminal button) तथा अन्य तन्त्रिका कोशिका के डेन्ड्राइट के मध्य एक युग्मानुबन्ध (synapse) होता है। अतः इस स्थान पर आवेग का संचरण विशेष रासायनिक पदार्थ ऐसीटिलकोलीन (acetylcholine) नामक न्यूरोहॉर्मोन का संचरण विशेष रासायनिक पदार्थ ऐसीटिलकोलीन (acetylcholine) नामक न्यूरोहॉर्मोन (neurohormone) के द्वारा होता है।

आवेग के प्राप्त होने पर अन्त्य बटन में उपस्थित स्रावी पुटिकाएँ (secretory vesicles) ऐसीटिलकोलीन स्रावित करती हैं। यही पदार्थ दूसरी तन्त्रिका कोशिका के डेण्ड्राइट (dendrites) में कार्यात्मक विभव (action potential) को स्थापित कर देता है। अब यही विभव, आवेग के रूप में अगले तन्त्रिका तन्तु की सम्पूर्ण लम्बाई में आगे बढ़ता जाता है। इस प्रकार, ऐसीटिलकोलीन एक रासायनिक दूत (chemical transmitter) की तरह कार्य करता है। बाद में, ऐसीटिलकोलीन कोएन्जाइम-ऐसीटिलकोलीनेस्टेरेज (acetylcholinesterase) द्वारा विघटित कर दिया जाता है।

चित्र – युग्मानुबन्ध पर आवेग का रासायनिक संवहन।

प्रश्न 4.
निम्नलिखित का नामांकित चित्र बनाइए –
(अ) न्यूरॉन
(ब) मस्तिष्क
(स) नेत्र
(द) कर्ण।
उत्तर:
(अ) न्यूरॉन की संरचना (Structure of Neuron)।
(ब) मस्तिष्क की संरचना (Structure of Brain)।
(स) नेत्र की संरचना (Structure of Eye)।
(द) कर्ण की संरचना (Structure of Ear)।
इन तीनों की संरचना हेतु प्रश्न संख्या 1 का उत्तर देखें।

(अ) न्यूरॉन की संरचना:

चित्र – एक ध्रुवीय तन्त्रिका कोशिका तथा उसके सम्पर्क

प्रश्न 5.
निम्नलिखित पर संक्षिप्त टिप्पणी लिखिए –
(अ) तन्त्रीय समन्वयनं
(ब) अग्रमस्तिष्क
(स) मध्यमस्तिष्क
(द) पश्चमस्तिष्क
(य) रेटिना
(र) कर्ण अस्थिकाएँ
(ल) कॉक्लिया
(व) ऑर्गन ऑफ कॉरटाई
(त) सिनैप्स।
उत्तर:
(अ) तन्त्रीय समन्वयन (Nervous – Coordination):
शरीर की विभिन्न क्रियाओं का नियन्त्रण तथा नियमन सूचना प्रसारण तन्त्र (communication system) द्वारा होता है। इसके अन्तर्गत तन्त्रिका तन्त्र (nervous system) तथा अन्तःस्रावी तन्त्र (Endocrine System) आते हैं। तन्त्रिका निर्माण तन्त्रिका कोशिकाओं (nerve cells) से होता है। ये कोशिकाएँ उत्तेजनशीलता एवं संवाहकता के लिए विशिष्टीकृत होती हैं।

ये आवेगों को संवेदांगों से ग्रहण करके केन्द्रीय तन्त्रिका तन्त्र तक और केन्द्रीय तन्त्रिका तन्त्र द्वारा होने वाली प्रतिक्रियाओं को अपवाहक (effectors) अंगों तक पहुँचाने का कार्य करती हैं। अपवाहक अंगों के अन्तर्गत मुख्यतया पेशियाँ तथा ग्रन्थियाँ आती हैं। केन्द्रीय तन्त्रिका तन्त्र उद्दीपनों की व्याख्या, विश्लेषण करके प्रतिक्रियाओं का निर्धारण करता है।

(ब) अग्रमस्तिष्क (Fore brain):
अग्र मस्तिष्क के तीन भाग होते हैं –

1. 1. घ्राण भाग
   2. सेरेब्रम तथा
   3. डाइएनसिफैलॉन।

1. घ्राण भाग: मनुष्य में घ्राण भाग अवशेषी होता है तथा अग्रमस्तिष्क का मुख्य भाग सेरिब्रम होता है।

2. प्रमस्तिष्क या सेरेब्रम (Cerebrum): मस्तिष्क का लगभग 2/3 भाग प्रमस्तिष्क होता है। प्रमस्तिष्क दो पालियों में बँटा होता है जिन्हें प्रमस्तिष्क गोलार्द्ध (cerebral hemispheres) कहते हैं। दोनों प्रमस्तिष्क गोलार्द्ध तन्त्रिका तन्तुओं की एक पट्टी द्वारा जुड़े रहते हैं जिसे कॉर्पस कैलोसम (corpus callosum) कहते हैं। प्रमस्तिष्क में तन्त्रिका कोशिकाएँ इस प्रकार स्थित होती हैं कि इनके कोशिकाकाय बाहर की ओर स्थित होते हैं।

इस भाग को प्रमस्तिष्क वल्कुट (cerebral cortex) कहते हैं भीतर की ओर तन्त्रिका कोशिकाओं पर अक्षतन्तु (axon) स्थित होते हैं। यह भाग प्रमस्तिष्क मध्यांश (cerebral medulla) कहलाता है। बाहरी भाग धूसर (ग्रे) रंग का होता है। इसे धूसर द्रव्य (grey matter) कहते हैं। भीतरी भाग श्वेत-(सफेद) रंग का होता है। इसे श्वेत द्रव्य (white matter) कहते हैं।

प्रमस्तिष्क की पृष्ठ सतह में तन्त्रिका तन्तुओं की अत्यधिक संख्या होने के कारण यह सतह अत्यधिक मोटी व वलनों वाली (folded) हो जाती है। इस सतह को नियोपैलियम (neopallium) कहते हैं। नियोपैलियम में उभरे हुए भागों को उभार या गायराई (gyri) तथा बीच के दबे भाग को खाँच या सल्काई (sulci) कहते हैं।

तीन गहरी दरारें प्रत्येक प्रमस्तिष्क गोलार्द्ध को चार मुख्य पालियों में बाँट देती हैं। इन्हें फ्रन्टल पालि (frontal lobe), पैराइटल पालि (parietal lobe), टैम्पोरल पालि (temporal lobe) तथा ऑक्सीपीटल पालि (occipital lobe) कहते हैं। प्रमस्तिष्क की गुहाओं को पार्श्व मस्तिष्क गुहा या पैरासील (paracoel or lateral ventricles) कहते हैं।

3. अग्रमस्तिष्क ‘पश्च या डाइएनसिफैलॉन (Diencephalon): यह अग्रमस्तिष्क का पिछला भाग है। इसका पृष्ठ भाग पतला होता है तथा अधर भाग मोटा होता है जिसे हाइपोथैलैमस (hypothalamus) कहते हैं। हाइपोथैलेमस की अधर सतह पर इन्फन्डीबुलम (infundibulum) से जुड़ी पीयूष ग्रन्थि होती है।

डाइएनसिफैलॉन की पृष्ठ सतह पर पीनियल काय (pineal body) तथा अग्र रक्त जालक, (anterior choroid plexus) पाया जाता है। डाइएनसिफैलॉन की गुहा तृतीय निलय (third ventricle) या डायोसील (diocoel) होती है, यह पार्श्व गुहाओं से मोनरो के छिद्र (foramen of Monaro) द्वारा जुड़ी रहती है।

(स) मध्यमस्तिष्क (Mid brain):
यह भाग स्तनियों में बहुत अधिक विकसित नहीं होता है। इसका पृष्ठ भाग चार दृक् पालियों के रूप में होता है, जिन्हें कॉर्पोरा क्याड्रिजेमिना (corpora quadrigemina) कहते हैं। मध्यमस्तिष्क के पार्श्व व अधर भाग में तन्त्रिका ऊतक की पट्टियाँ होती हैं जिन्हें क्रूरा सेरेब्राई (crura cerebri) कहते हैं। ये पश्चमस्तिष्क को अग्रमस्तिष्क से जोड़ने का कार्य करती हैं। यहाँ दृक् तन्त्रिकाएँ एक-दूसरे को क्रॉस करके, ऑप्टिक कियाज्मा (optic chiasma) बनाती है। मध्यमस्तिष्क की सँकरी गुहा को आइटर (iter) कहते हैं, जो तृतीय निलय को चतुर्थ निलय (fourth ventricle) से जोड़ती हैं।

(द) पश्चमस्तिष्क (Hind brain):
यह मस्तिष्क का पश्च भाग है। इसे मस्तिष्क वृन्त (brain stalk) भी कहते हैं। पश्च मस्तिष्क के दो भाग होते हैं –

(i) अनुमस्तिष्क (cerebellum)
(ii) मस्तिष्क पुच्छ या मेडुला ऑब्लांगेटा (medulla oblongata)।

(i) अनुमस्तिष्क (Cerebellum):
यह प्रमस्तिष्क के पिछले भाग से सटा रहता है। अनुमस्तिष्क दो पार्श्व गोला? (lateral hemispheres) का बना होता है। अनुमस्तिष्क में बाहरी धूसर द्रव्य तथा आन्तरिक श्वेत द्रव्य होता है। श्वेत द्रव्य में स्थान-स्थान पर धूसर. द्रव्य प्रवेश करके वृक्ष की शाखाओं जैसी रचना बनाता है। इसे प्राणवृक्ष या आरबर विटी (arbor vitae) कहते हैं। अनुमस्तिष्क में गुहा अनुपस्थित होती है। अनुमस्तिष्क के अधर भाग में श्वेत द्रव्य की एक पट्टी होती है जिसे पोंस वेरोली (pons varolli) कहते हैं।

(ii) मस्तिष्क पुच्छ या मेडुला ऑब्लांगेटा (Medulla Oblongata):
यह मस्तिष्क का सबसे पिछला भाग है जो आगे मेरुरज्जु के रूप में कपाल गुहा से बाहर निकलता है। मेडुला की पृष्ठ भित्ति पर पश्च रक्त जालक (posterior choroid plexus) स्थित होता है। मेडुला की गुहा को चतुर्थ निलय या मेटासील (fourth ventricle or metacoel) कहते हैं।

(य) रेटिना (Retina):
यह नेत्र गोलक की सबसे भीतरी पर्त होती है। यह प्रकाश संवेदी स्तर होता है। रेटिना का वर्णक स्तर रक्तपटल (choroid layer) से लगा होता है। रेटिना की स्थिति की भीतरी पर्त तन्त्रिका संवेदी होती है। इसका निर्माण निम्नलिखित तीन पर्तों से होता है –

(i) शलाकाओं व शंकुओं का स्तर (Layer of Rods and Cones):
शलाकाएँ (rods) तथा शंकु (cones) रूपान्तरित तन्त्रिका कोशिका होते हैं। शलाकाओं में दृष्टि पर्पल (visual purple) नामक चमकदार वर्णक होता है जिसे रोडोप्सिन (rhodopsin) कहते हैं। रोडोप्सिन का निर्माण वर्णक रेटिनीन (retinene) तथा प्रोटीन ऑप्सिन या स्कॉटोप्सिन (opsin or scotopsin) से होता है। रेटिनीन के संश्लेषण के लिए विटामिन ‘ए’ की आवश्यकता होती है।

शंकुओं में दृष्टि वायलेट (visual violet) नामक वर्णक होता है जिसे आयोडोप्सिन (iodopsin) कहते हैं। आयोडोप्सिन का निर्माण रेटिनीन तथा फोटोप्सिन (photopsin) से होता है। शंकु रंगों का ज्ञान कराते हैं। शलाकाएँ अँधेरे व प्रकाश में भेद करती हैं। ये मन्द प्रकाश में भी कार्य कर सकती हैं। मुर्गी में केवल शंकु (cones) तथा उल्लू में केवल शलाकाएँ (rods) पाई जाती हैं।

(ii) द्विध्रुवीय-न्यूरॉन का स्तर (Layer of Bipolar Neurons):
इस स्तर में द्विध्रुवीय न्यूरॉन्स की एक कतार होती हैं।

(iii) गुच्छकीय कोशिकाओं का स्तर (Layer of Ganglionic Cells):
इस स्तर में भी गुच्छकीय कोशिकाओं की एक कतार होती है। गुच्छकीय कोशिकाओं के अक्षतन्तु (axons) परस्पर मिलकर दृक् तन्त्रिका (optic nerve) का निर्माण करते हैं।

चित्र – रेटिना की रचना का परिवर्द्धित रेखाचित्र

दृक् तन्त्रिका नेत्र गोलक के तीनों स्तरों को भेदती हुई, नेत्र कोटर में बने दृक् छिद्र (optic foramen) द्वारा होकर मस्तिष्क की ओर चली जाती है। जिस स्थान से दृक् तन्त्रिका रेटिना से निकलती हैं, वहाँ प्रतिबिम्ब निर्माण नहीं होता। इस स्थान को अन्ध बिन्दु (blind spot) कहते हैं। नेत्र की मध्य लम्ब अक्ष (optical axis) पर स्थित रेटिना के मध्य भाग को मध्य क्षेत्र (area centralis) कहते हैं। इस भाग को पीत बिन्दु (yellow spot) या मैकुला ल्यूटिया (macula lutea) भी कहते हैं। यहाँ उपस्थित एक छोटे से गर्त को फोविया सेन्ट्रैलिस (fovea centralis) कहते हैं। पीत बिन्दु क्षेत्र में सबसे स्पष्ट प्रतिबिम्ब बनता है।

(र) कर्ण अस्थिकाएँ (Ear Ossicles):
मध्यकर्ण में तीन कर्ण अस्थिकाएँ चल सन्धियों द्वारा परस्पर जुड़ी रहती हैं। इन्हें क्रमश; मैलियस (malleus), इन्कस (incus) और स्टैपीज (stapes) कहते हैं।

(i) मैलियस (Malleus):
यह हथौड़ीनुमा होती है। इसका बाह्य सँकरा भाग कर्णपटह से तथा भीतरी चौड़ा सिरा इन्कस से जुड़ा होता है।

(ii) इन्कस (Incus):
यह निहाई (anvil) के आकार की होती है। इसका बाहरी चौड़ा सिरा मैलियस से तथा भीतरी सँकरा भाग स्टैपीज से जुड़ा होता है।

(iii) स्टैपीज (Stapes):
यह रकाब (stirrup) के आकार की होती है। इसका संकरा सिरा इन्कस से और चौड़ा सिरा फेनेस्ट्रा ओवैलिस (fenestra ovalis) से लगा होता है। कर्ण अस्थिकाएँ कर्णपटह पर होने वाले ध्वनि कम्पनों को अधिक प्रबल करके फेनेस्ट्रा ओवैलिस द्वारा अन्त:कर्ण में पहुँचाती हैं।

चित्र – कॉक्लिया की अनुप्रस्थ काट

(ल) कॉक्लिया (Cochlea):
मनुष्य का अन्तःकर्ण या कलागहन (membranous labyrinth) दो मुख्य भागों से बना होता है। यूट्रिकुलस (utriculus) तथा सैक्यूलस (sacculus) सैक्यूलस से स्प्रिंग की तरह कुण्डलित कॉक्लिया निकलता है। यह नलिकारूपी होता है। इसमें 2\(\frac{3}{4}\) कुण्डलन होते हैं। इसके चारों ओर अस्थिल कॉक्लिया का आवरण होता है।

कॉक्लिया की नलिका अस्थिल लेबिरिन्थ की भित्ति से जुड़ी रहती है जिससे अस्थिल लेबिरिन्थ की गुहा दो वेश्मों में बँट जाती है। पृष्ठ वेश्म को स्कैला वेस्टीबुली (scala vestibuli) कहते हैं तथा अधर वेश्म को स्कैला टिम्पैनी (scala tympani) कहते हैं। इन दोनों वेश्म के मध्य कॉक्लिया का वेश्म स्कैला मीडिया (scala media) होता है।

(व) ऑर्गन ऑफ कॉरटाई (Organ of Corti):
कॉक्लिया नलिका की गुहा स्कैला मीडिया की पतली पृष्ठ भित्ति रीसनर्स कला (Reissner’s membrane) कहलाती है। अधर भित्ति मोटी होती है। इसे बेसीलर कला (basilar membrane) कहते हैं। बेसीलर कला के मध्य में कॉरटाई का अंग (organ of Corti) होता है। इसमें अवलम्ब कोशिकाओं के बीच-बीच में संवेदी कोशिकाएँ होती हैं।

प्रत्येक संवेदी कोशिका के स्वतन्त्र तल पर स्टीरियोसीलिया (stereocilia) होते हैं। कॉरटाई के अंग के ऊपर टेक्टोरियल कला (tectorial membrane) स्थित होती है। संवेदी कोशिकाओं से निकले तन्त्रिका तन्तु मिलकर श्रवण · तन्त्रिका (auditory nerve) का निर्माण करते हैं। कॉरटाई के अंग ध्वनि के उद्दीपनों को ग्रहण करते हैं।

चित्र – कॉरटाई के अंग की विस्तृत रचना

(त) सिनैप्स (Synapse):
प्रत्येक तन्त्रिका कोशिका का अक्षतन्तु (axon) अपने स्वतन्त्र छोर, पर टीलोडेन्ड्रिया (telodendria) या एक्सॉन अन्तस्थ (axon terminals) नामक शाखाओं में बँट जाता है। प्रत्येक शाखा का अन्तिम छोर घुण्डीनुमा होता है। इसे सिनैप्टिक बटन (synaptic button) कहते हैं। ये घुण्डिंया समीपवर्ती तन्त्रिका कोशिका के डेण्ड्राइट्स के साथ सन्धि बनाती हैं। इन संधियों को सिनैप्स या युग्मानुबन्ध कहते हैं।

युग्मानुबन्ध पर सूचना लाने वाली तन्त्रिका कोशिका को पूर्व सिनैष्टिक (presynaptic) तथा सूचना ले जाने वाली तन्त्रिका कोशिका को पश्च सिनैप्टिक (post synaptic) कहते हैं। इनके मध्य भौतिक सम्पर्क नहीं होता। दोनों के मध्य लगभग 20 से 40 m u का दरारनुमा सिनैप्टिक विदर होता है। इसमें ऊतक तरल भरा होता है। सिनैप्टिक विदर से उद्दीपन या प्रेरणाओं का संवहन तन्त्रिका संचारी पदार्थों; जैसे-ऐसीटिलकोलीन (acetylcholine) के द्वारा होता है।

प्रश्न 6.
निम्न पर संक्षिप्त टिप्पणी दीजिए –
(अ) सिनैप्टिक संचरण की क्रियाविधि
(ब) देखने की प्रक्रिया
(स) श्रवण की प्रक्रिया।
उत्तर:
(अ) सिनैप्टिक संचरण की क्रियाविधि (Mechanism of Synaptic Transmission):
शेरिंगटन (Sherrington) ने दो तन्त्रिका कोशिकाओं के सन्धि स्थलों को युग्मानुबन्ध (synapsis) कहा। इसका निर्माण पूर्व सिनैप्टिक तथा पश्च सिनैप्टिक तन्त्रिका तन्तुओं से होता है।

युग्मानुबन्ध में पूर्व सिनैप्टिक तन्त्रिका के एक्सॉन या अक्षतन्तु के अन्तिम छोर पर स्थित सिनैप्टिक बटन (synaptic button) तथा पश्च सिनैप्टिक तन्त्रिका कोशिका के डेन्ड्राइट्स के मध्य सन्धि होती है। दोनों के मध्य सिनैप्टिक विदर (synaptic cleft) होता है, इससे उद्दीपन विद्युत, तरंग के रूप में प्रसारित नहीं हो पाता।

सिनैप्टिक बटन या घुण्डियों में सिनैप्टिक पुटिकाएँ (synaptic vesicles) होती हैं। ये तन्त्रिका संचारी पदार्थ (neurotransmitters) से भरी होती है। उद्दीपन या प्रेरणा के क्रियात्मक विभव के कारण Ca²⁺ ऊतक द्रव्य से सिनैप्टिक घुण्डियों में प्रवेश करते हैं तो सिनैप्टिक घुण्डियों से तन्त्रिका संचारी पदार्थ मुक्त होता है। यह तन्त्रिका संचारी पदार्थ पश्च सिनैप्टिक, तन्त्रिका के डेन्ड्राइट पर क्रियात्मक विभव को स्थापित कर देता है, इसमें लगभग 0.5 मिली सेकण्ड का समय लगता है।

प्रेरणा प्रसारण या क्रियात्मक विभव के स्थापित हो जाने के पश्चात् एन्जाइम्स द्वारा तन्त्रिका संचारी पदार्थ का विघटन कर दिया जाता है, जिससे अन्य प्रेरणा को प्रसारित किया जा सके। सामान्यतया सिनैप्टिक पुटिकाओं से ऐसीटिलकोलीन (acetylcholine) नामक तन्त्रिका संचारी पदार्थ मुक्त होता है। इसका विघटन ऐसीटिलकोलीनेस्टीरेज (acetylcholinesterase) एन्जाइम द्वारा होता है।

एपिनेफ्रीन (epinephrine) डोपामीन (dopamine), हिस्टैमीन (histamine), HIHChefca (somatostatine) 3tif Taref अन्य तन्त्रिका संचारी पदार्थ हैं। ग्लाइसीन (glycine) गामा-ऐमीनोब्यूटाइरिक (gamma aminobutyric acid-GABA) आदि तन्त्रिका संचारी पदार्थ प्रेरणाओं के प्रसारण को रोक देते हैं।

(ब) देखने की प्रक्रिया (Mechanism of Vision):
नेत्र कैमरे की भाँति कार्य करते हैं। ये प्रकाश की 380 से 760 नैनोमीटर तरंगदैर्ध्य (wave-length) की किरणों की ऊर्जा को ग्रहण करके इसे तन्त्रिका तन्तु के क्रिया विभव (action potential) में बदल देते हैं।

नेत्र की क्रिया-विधि (Working of Eye):
जब उचित आवृत्ति की प्रकाश तरंगें कॉर्निया पर पड़ती हैं, तब कॉर्निया तथा तेजोजल प्रकाश किरणों का अपवर्तन (refraction) कर देते हैं। ये किरणें तारे से होकर लेन्स पर पड़ती हैं। लेन्स इनका पूर्ण अपवर्तन कर देता है और उल्टा प्रतिबिम्ब रेटिना पर बना देता है। आइरिस तारे को छोटा या बड़ा करके प्रकाश की मात्रा का नियन्त्रण करता है। तीव्र प्रकाश में तारा सिकुड़ जाता है तथा कम प्रकाश नेत्र के भीतर प्रवेश करता है। कम प्रकाश में तारा फैल जाता है और अधिक प्रकाश नेत्र के भीतर प्रवेश करता है।

नेत्र द्वारा समायोजन (Accommodation by Eye):
सीलियरी काय तथा निलम्बन स्नायु (suspensory ligaments) लेन्स के फोकस में अन्तर लाकर वस्तु के प्रतिबिम्ब को रेटिना पर केन्द्रित करते हैं। सामान्य अवस्था में नेत्र दूर की वस्तु देखने के लिए समायोजित रहता है। इस समय सीलियरी काय शिथिल (relaxed) रहता है तथा निलम्बन स्नायु तना रहता है। इससे लेन्स की फोकस दूरी अधिक हो जाती है और दूर की वस्तु का स्पष्ट प्रतिबिम्ब बनता है।

चित्र – नेत्र द्वारा प्रतिबिम्ब का निर्माण
पास की वस्तु देखने के लिए सीलियरी काय में संकुचन तथा निलम्बन स्नायु में शिथिलन होता है। इससे लेन्स छोटा व मोटा हो जाता है तथा इसकी फोकस दूरी कम हो जाती है। इससे पास की वस्तु का स्पष्ट प्रतिबिम्ब बनता है।

चित्र – नेत्र द्वारा समायोजन

प्रकाश-रासायनिक परिवर्तन (Photo – chemical Changes):
जब विशिष्ट तरंगदैर्ध्य वाली प्रकाश की किरणें रेटिना पर पड़ती हैं, तब वे शलाकाओं तथा शंकुओं में उपस्थित रसायनों में परिवर्तन करती हैं।

चित्र – शलाका में प्रकाश-रासायनिक परिवर्तन जब प्रकाश की किरणें शलाकाओं के रोडोप्सिन पर पड़ती है, तब यह रेटिनीन (retinene) तथा ऑप्सिन (opsin) में टूट जाता है। अन्धकार में शलाकाओं में एन्जाइम्स की सहायता से रेटिनीन तथा ऑप्सिन रोडोप्सिन का संश्लेषण करते हैं। यही कारण है कि जब हम तीव्र प्रकाश से अन्धकार में जाते हैं, तब एकदम कुछ दिखाई नहीं देता किन्तु धीरे-धीरे स्पष्ट दिखाई देने लगता है।

शंकुओं में आयोडोप्सिन उपस्थित होता है। इसका वर्णक घटक रेटिनीन तथा प्रोटीन घटक फोटोप्सिन होता है। शंकु तीन प्रारम्भिक रंगों को ग्रहण करते हैं, जो लाल, नीला व हरा होते हैं। इन्हीं तीन प्रकार के शंकुओं द्वारा विभिन्न मात्रा में उद्दीपन ग्रहण से अन्य रंगों का ज्ञान होता है। मनुष्य व दूसरे प्राइमेट्स में दोनों नेत्रों द्वारा एक ही प्रतिबिम्ब बनता है। ऐसी दृष्टि को द्विनेत्री दृष्टि (binocular vision) कहते हैं।

(स) श्रवण की प्रक्रिया (Mechanism of Hearing):
कर्ण के निम्नलिखित प्रमुख दो कार्य होते हैं –

(i) कर्ण का प्राथमिक कार्य शरीर का स्थैतिक तथा गतिक सन्तुलन बनाए रखना तथा
(ii) ध्वनि ग्रहण करना अर्थात् श्रवण करना।

अन्त:कर्ण के कलागहन के कॉक्लिया में स्थित कॉरटाई का अंग ध्वनि के उद्दीपनों को ग्रहण करने के लिए उत्तरदायी है। श्रवण क्रिया में कर्ण द्वारा एक विशेष आवृत्ति की ध्वनि कम्पनों को ग्रहण करके कॉरटाई के अंग में स्थित संवेदी कोशिकाओं तक भेजा जाता है।

संवेदी कोशिकाएँ इन तरंगों को तन्त्रिका के क्रिया विभव में परिवर्तित कर देती है। मस्तिष्क के ध्वनि वल्कुट (auditory cortex) सुनने का कार्य करता है। मनुष्य का कर्ण 16 से 20,000 साइकिल प्रति सेकण्ड की ध्वनि तरंगों को ग्रहण कर सकता है। बाह्य कर्ण पल्लव ध्वनि तरंगों को कर्ण कुहर में भेज देता है। ध्वनि तरंगें कर्णपटह में कम्पन्न उत्पन्न करती हैं।

मध्य कर्ण की कर्ण अस्थिकाओं द्वारा कर्ण पटह से कम्पन्न अण्डाकार गवाक्ष के ऊपर मढ़ी झिल्ली पर पहुंचते हैं। इसके फलस्वरूप अन्त:कर्ण के स्कैला वेस्टीबुली (scala vestibuli) के परिलसिका में कम्पन्न होने लगता है। यहाँ के कम्पन्न स्कैला टिम्पैनी (scala tympani) के परिलसीका में पहुंचते हैं। रीसनर्स कला तथा बेसीलर कला में कम्पन्न होने से स्कैला मीडिया (scala media) के अन्त:लसीका में कम्पन्न होने लगता है जिससे कॉरटाई के अंग के संवेदी रोमों में कम्पन्न होने लगता है।

संवेदी रोमों के कम्पन्न टेक्टोरियल कला में कम्पन्न उत्पन्न करके ध्वनि संवेदना की प्रेरणा उत्पन्न कर देते हैं। श्रवण तन्त्रिका द्वारा ध्वनि संवेदना मस्तिष्क के ध्वनि वल्कुट (auditory cortex) तक पहुँच जाती है। ध्वनि की तीव्रता संवेदी रोमों के कम्पन की तीव्रता से ज्ञात होती है। ध्वनि तरंगों के कम्पन वृत्ताकार गवाक्ष की झिल्ली से टकराकर समाप्त हो जाते हैं।

चित्र – कर्ण में ध्वनि तरंगों का मार्ग

प्रश्न 7.
(अ) आप किस प्रकार किसी वस्तु के रंग का पता लगाते हैं?
(ब) हमारे शरीर का कौन-सा भाग शरीर का सन्तुलन बनाए रखने में मदद करता है?
(स) नेत्र किस प्रकार रेटिना पर पड़ने वाले प्रकाश का नियमन करते हैं?
उत्तर:
(अ) नेत्र गोलक की रेटिना तन्त्रिका संवेदी (neurosensory) होती है। इसमें दृष्टि शलाकाएँ (rods) तथा दृष्टि शंकु (cones) पाए जाते हैं। शंकुओं में आयोडोप्सिन (iodopsin) दृष्टि वर्णक पाया जाता है। तीव्र प्रकाश में शंकु विभिन्न रंगों को ग्रहण करते हैं। शंकु तीन प्राथमिक रंगों लाल, हरे व नीले से सम्बन्धित भिन्न-भिन्न प्रकार के होते हैं। ये इन प्राथमिक रंगों को ग्रहण करते हैं। इन प्राथमिक रंगों के मिश्रण से विभिन्न रंगों का ज्ञान होता है।

(ब) अन्त:कर्ण की अर्द्धचन्द्राकार नलिकाओं के तुम्बिका (ampulla), सैक्यूलस तथा यूट्रिकुलस शरीर का सन्तुलन बनाने का कार्य करती है। यूट्रिकुलस तथा सैक्टूलस के मैकुला तथा अर्द्धचन्द्राकार नलिकाओं के तुम्बिका में स्थित संवेदी कूटों द्वारा गतिक सन्तुलन (dynamic equilibrium) नियन्त्रित होता है।

जब शरीर एक ओर को झुक जाता है, तब ऑटोकोनिया उसी ओर चले जाते हैं जहाँ वे संवेदी कूटों को उद्दीपन प्रदान करते हैं। इससे तन्त्रिका आवेग उत्पन्न होता है और मस्तिष्क में शरीर के झुकने.की सूचना पहुँच जाती है। मस्तिष्क प्रेरक तन्त्रिकाओं द्वारा सम्बन्धित पेशियों को सूचना भेजकर शरीर का सन्तुलन बनाता हैं।

(स) रेटिना (retina) पर पड़ने वाले प्रकाश की मात्रा का नियमन उपतारा (iris) द्वारा किया जाता है। यह एक मुद्राकार, चपटा, मिलैनिन वर्णकयुक्त तन्तुपट (diaphragm) के रूप में होता है। इसके गोल छिद्र को तारा या पुतली (pupil) कहते हैं। उपतारा (iris) में अरेखित अरीय प्रसारी पेशियाँ (radial dilatory muscles) तथा अरेखित वर्तुल अवरोधिनी पेशियाँ (circular sphincter muscles) होती है।

अरीय पेशियों के संकुचन से पुतली का व्यास बढ़ जाता है और वर्तुल पेशियों के संकुचन से पुतली का व्यास घट जाता है। इस प्रकार ये पेशियाँ क्रमश: मन्द प्रकाश और तीव्र प्रकाश में संकुचित होकर रेटिना पर पड़ने वाले प्रकाश की मात्रा का नियमन करती हैं।

चित्र – उपतारा (iris) में पेशियों का विन्यास

प्रश्न 8.
(अ) सक्रिय विभव उत्पन्न करने में Na⁺ की भूमिका का वर्णन कीजिए।
(ब) सिनैप्स पर न्यूरोट्रान्समीटर मुक्त करने में Ca⁺⁺ की भूमिका का वर्णन कीजिए।
(स) रेटिना पर प्रकाश द्वारा आवेग उत्पन्न होने की क्रियाविधि का वर्णन कीजिए।
(द) अन्तःकर्ण में ध्वनि द्वारा तन्त्रिका आवेग उत्पन्न होने की क्रियाविधि का वर्णन कीजिए।
उत्तर:
(अ) सक्रिय विभव उत्पन्न करने में Na⁺ की भूमिका (Role of Na⁺ in the generation of Action Potential):
उद्दीपन के फलस्वरूप तन्त्रिकाच्छद या न्यूरीलेमा की Na⁺ के लिए पारगम्यता बढ़ जाने से Na⁺ ऊतक तरल से ऐक्सोप्लाज्म में तेजी से पहुँचने लगते हैं। इसके फलस्वरूप तन्त्रिका तन्तु का विध्रुवीकरण हो जाता है और तन्त्रिका तन्तु का विश्राम कला विभव क्रियात्मक कला विभव में बदलकर प्रेरणा प्रसारण में सहायता करता है।

(ब) सिनैप्स पर न्यूरोट्रान्समीटर मुक्त करने में Ca⁺⁺ की भूमिक (Role of Ca⁺⁺ to release Neurotransmitters of Synapsis):
जब कोई तन्त्रिकीय प्रेरणा क्रियात्मक विभव के रूप में सिनैप्टिक घुण्डी पर पहुँचती है तो Ca⁺⁺ ऊतक तरल से सिनैप्टिक घुण्डी में प्रवेश कर जाते हैं। इनके प्रभाव से सिनैप्टिक घुण्डी की सिनैप्टिक पुटिकाएँ इसकी कला से जुड़ जाती हैं।

इससे सिनैप्टिक पुटिकाओं से तन्त्रिका संचारी पदार्थ (न्यूरोट्रान्समीटर) मुक्त होकर सिनैप्टिक विदर के ऊतक तरल में पहुँच जाता है और पश्च सिनैप्टिक तन्त्रिका कोशिका के ड्रेन्ड्राइट्स पर रासायनिक उद्दीपन द्वारा क्रियात्मक विभव को स्थापित कर देता है।

(स) रेटिना पर प्रकाश द्वारा आवेग उत्पन्न होने की fatenfalfa (Mechanism of generation of Light Impulse in the Retina) – प्रश्न 6 ‘ब’ के अन्तर्गत प्रकाश-रासायनिक परिवर्तन (photo-chemical changes) का विवरण देखिए।

(द) अन्तःकर्ण में ध्वनि द्वारा तन्त्रिका आवेग उत्पन्न होने की क्रियाविधि (Mechanism through which a Sound produces a Nerve Impulse in the Internal Ear) – प्रश्न 6 ‘स’ के अन्तर्गत देखिए।

प्रश्न 9.
निम्न के बीच में अन्तर बताइए –
(अ) आच्छादित और अनाच्छादित तंत्रिकाक्ष
(ब) द्रुमाक्ष्य और तन्त्रिकाक्ष
(स) शलाका और शंकु
(द) थैलेमस तथा हाइपोथैलेमस
(य) प्रमस्तिष्क और अनुमस्तिष्क।
उत्तर:
(अ) आच्छादित और अनाच्छादित तन्त्रिका तन्तु (Myelinated and Non-myelinated Neuron):

(ब) द्रुमाक्ष्य या गुमाश्म या वृक्षाभ और तन्त्रिकाक्ष में अन्तर (Difference between Den – drites and Axons):

(स) शलाका और शंकु में अन्तर (Difference between Rods and Cones):

(द) थैलेमस तथा हाइपोथैलेमस में अन्तर (Difference between Thalamus and Hypothalamus):

(य) प्रमस्तिष्क तथा अनुमस्तिष्क में अन्तर (Difference between Cerebrum and Cerebellum):

प्रश्न 10.
(अ) कर्ण का कौन-सा भाग ध्वनि की पिच का निर्धारण करता है?
(ब) मानव मस्तिष्क का सर्वाधिक विकसित भाग कौन-सा है?
(स) केन्द्रीय तन्त्रिका तन्त्र का कौन-सा भाग मास्टर क्लॉक की तरह कार्य करता है?
उत्तर:
(अ) कॉरटाई के अंग (organ of Corti) की संवेदनग्राही कोशिकाएँ ध्वनि की पिच का निर्धारण करती हैं तथा उद्दीपनों को ग्रहण करके श्रवण तन्त्रिका (auditory nerve) में प्रेषित करती हैं।
(ब) प्रमस्तिष्क (cerebrum) मस्तिष्क का सर्वाधिक विकसित भाग है। यह मस्तिष्क का लगभग 80% भाग बनाता है।
(स) मस्तिष्क मास्टर क्लॉक की तरह कार्य करता है।

प्रश्न 11.
कशेरुकी के नेत्र का वह भाग जहाँ से दृक् तन्त्रिका (optic nerve) रेटिना से बाहर निकलती है, क्या कहलाता है –
(अ) फोविया (Fovea)
(ब) आइरिस (Iris)
(स) अन्ध बिन्दु (Blind spot)
(द) ऑप्टिक किएज्मा (चाक्षुष किएज्मा)।
उत्तर:
(स) अन्ध बिन्दु (Blind spot)।

प्रश्न 12.
निम्नलिखित में भेद स्पष्ट कीजिए –
(अ) संवेदी तन्त्रिका एवं प्रेरक तन्त्रिका।
(ब) आच्छादित एवं अनाच्छादित तन्त्रिका तन्तु में आवेग संचरण।
(स) ऐक्विअस ह्यूमर ( नेत्रोद) एवं विट्रियस ह्यमर (काचाभ द्रव)।
(द) अन्ध बिन्दु एवं पीत बिन्दु।
(य) कपालीय तन्त्रिकाएँ एवं मेरु तन्त्रिकाएँ।
उत्तर:
(अ) संवेदी तन्त्रिका एवं प्रेरक तन्त्रिका में अन्तर (Difference between Sensory and Motor Nerve):

(ब) आच्छादित एवं अनाच्छादित तन्त्रिका तन्तु में आवेग संचरण में अन्तर (Difference between Conduction of Nerve Impulse in a Myelinated and Non Myelinated Nerve Fibres):

(स) एक्विअसामर (नेत्रोद) एवं विट्रियस ह्यमर (काचाभ द्रव) में अन्तर (Difference between Aqueous and Vitreous Humour):

(द) अन्ध बिन्दु एवं पीत बिन्दु में अन्तर (Difference between Blind Spot and Yellow Spot):

(य) कपालीय तन्त्रिकाओं एवं मेरु तन्त्रिकाओं में अन्तर (Difference between Cranial Nerves and Spinal Nerves):

Bihar Board 12th Economics Model Papers

Bihar Board 12th Economics Model Question Paper 4 in English Medium

Time : 3 Hour. 15 Min
Full Marks : 100

Instructions

1. Candidates are required to give their answers in their own words as far as practicable.
2. Figures in the right hand margin indicate full marks.
3. 15 minutes of extra time has been allotted for the candidate to read the questions carefully.
4. This question paper has two sections : Section-A and Section-B.
5. In Section-A, there are 50 objective type questions which are compulsory, each carrying 1 mark. Darken the circle with black/blue ball pen against the correct option on OMR Sheet provided to you Do. not use Whitener/Liquid/Blade/Nail on OMR Sheet, otherwise the result will be treated as invalid.
6. In Section-B, there are Non-objective type questions. There are 25 Short answer type questions, out of which any 15 questions are to be answered. Each question carries 2 marks. Apart forms this, there are 08 Long answer type questions, out-of which any 04 of them are to be answered. Each questions carries 5 marks.
7. Use of any electronic device is prohibited.

Percent off calculator – discover the percent of a number or find a number given a percent.

Objective Type Questions

Question No. -1 to 50 have four options provided, out of which only one is correct. You have to mark, your selected option, on the OMR-Sheet. Each questiion carries 1 (one) mark. [50 x 1 = 50]

Question 1.
Who. said “Economics is a science of Wealth” ?
(a) Marshall
(b) Robbins
(c) Adam Smith
(d) J. K. Mehta
Answer:
(c) Adam Smith

Question 2.
Micro-economics includes __________
(a) individual unit
(b) small units
(c) individual price determination
(d) all of these
Answer:
(d) all of these

Question 3.
Which of the following statements is true ?
(a) Human wants are infinite
(b) Resources are limited
(c) Scarcity problem gives birth to choice
(d) All of these
Answer:
(d) All of these

Question 4.
The name of the curve which shows economic problem is __________
(a) Production curve
(b) Demand curve
(c) Indifference curve
(d) Production possibility curve
Answer:
(c) Indifference curve

Question 5.
With rise in price of, coffee the demand of tea __________
(a) rises
(b) falls
(c) remains stable
(d) none of these
Answer:
(a) rises

Question 6.
Goods, which can be alternatively used, are called __________
(a) Complementary goods
(b) Substitute goods
(c) Comfort goods
(d) None of these
Answer:
(b) Substitute goods

Question 7.
Long-run production function is related to __________
(a) Law of demand
(b) Law of increasing returns
(c) Law of returns of scale
(d) Elasticity of demand
Answer:
(c) Law of returns of scale

Question 8.
The alternative name of opportunity cost is __________
(a) Economic cost
(b) Equilibrium price
(c) Marginal cost
(d) Average cost
Answer:
(a) Economic cost

Question 9.
The first condition of firm’s equilibrium is __________
(a) MC = MR
(b) MR = TR
(c) MR = AR
(d) AC = AR
Answer:
(a) MC = MR

Question 10.
The reason of decrease in supply is __________
(a) increase in production cost
(b) increase in price substitutes
(c) fall in number of firms in the industry
(d) all of these
Answer:
(d) all of these

Question 11.
When supply increase more with a result of small increase in price, the nature of supply will be __________
(a) elastic
(b) inelastic
(c) perfectly inelastic
(d) perfectly elastic
Answer:
(a) elastic

Question 12.
What does a monopolist market show?
(a) production process
(b) Distribution system
(c) Nature of market
(d) None of these
Answer:
(c) Nature of market

Question 13.
Market situation where there is only one buyer is __________
(a) Monopoly
(b) Monopsony
(c) Duopoly
(d) None of these
Answer:
(b) Monopsony

Question 14.
Which factor determines equilibrium price ?
(a) Demand for commodity
(b) Supply of commodity
(c) Both (a) and (b)
(d) None of these
Answer:
(c) Both (a) and (b)

Question 15.
Market price is found in __________
(a) short period market
(b) long period market
(c) very long period market
(d) none of these
Answer:
(a) short period market

Question 16.
Which is the component of factor price deter-mination ?
(a) Rent
(b) Wages
(c) Interest
(d) All of these
Answer:
(d) All of these

Question 17.
General price level is studied in __________
(a) Micro-Economics
(b) Macro-Economics
(c) Both (a) and (b)
(d) None of these
Answer:
(b) Macro-Economics

Question 18.
Which one is the limitation of Macro Economics ?
(a) Collective Economic Paradox
(b) Ignores Individual Units
(c) Both (a) and (b)
(d) None of these
Answer:
(c) Both (a) and (b)

Question 19.
Macro-Economics studies __________
(a) Employment opportunities in economy
(b) Theory of supply of commodities
(c) Elasticity of demand in scooter
(d) Price of wheat in market
Answer:
(a) Employment opportunities in economy

Question 20.
Primary sector includes __________
(a) Agriculture
(b) Retail trading
(c) Small industries
(d) All of these
Answer:
(a) Agriculture

Question 21.
Which one is included in National Income ?
(a) Rent, wage, interest
(b) Rent, wage, salary
(c) Rent, profit, interest
(d) Rent, wage, salary, interest, profit
Answer:
(d) Rent, wage, salary, interest, profit

Question 22.
Depreciation expenses are included in __________
(a) GNPMP
(b) NNPMP
(c) NNPFC
(d) None of these
Answer:
(c) NNPFC

Question 23.
Which service is included in Tertiary Sector ?
(a) Mining
(b) Construction
(c) Communication
(d) Animal Husbandry
Answer:
(c) Communication

Question 24.
Which one is a component of profit ?
(a) Dividend
(b) Undistributed Profit
(c) Corporate Profit Tax
(d) All of these
Answer:
(d) All of these

Question 25.
The function of money is __________
(a) Medium of exchange
(b) Measure of value
(c) Store of value
(d) All of these
Answer:
(d) All of these

Question 26.
“Money is what money does.” Who said it ?
(a) Keynes
(b) Prof. Thomas
(c) Hawtrey
(d) Hartley Withers
Answer:
(d) Hartley Withers

Question 27.
Which one is the Bank of the Public ?
(a) Commercial Bank
(b) Central Bank
(c) Both (a) and (b)
(d) None of these
Answer:
(a) Commercial Bank

Question 28.
Credit money is increased when CRR __________
(a) falls (b) rises
(c) both (a) and (b)
(d) none of these
Answer:
(a) falls (b) rises

Question 29.
Reserve Bank of India was established in __________
(a) 1947
(b) 1935
(c) 1937
(d)1945
Answer:
(b) 1935

Question 30.
Monetary policy is related with __________
(a) Public expenditure
(b) Taxes
(c) Public debt
(d) Open market operations
Answer:
(d) Open market operations

Question 31.
Banking Ombudsman Scheme was announced in the year __________
(a) 1990
(b) 1995
(c) 1997
(d) 2000
Answer:
(b) 1995

Question 32.
Who is the custodian of Indian Banking system ?
(a) Reserve Bank of India
(b) State Bank of India
(c) Unit Trust of India
(d) LIC of India
Answer:
(a) Reserve Bank of India

Question 33.
“Supply creates its own demand.” Who said it ?
(a) J.B. Say
(b) J.S. Mill
(c) Keynes
(d) Ricardo
Answer:
(a) J.B. Say

Question 34.
Which statement is true ?
(a) MPC + MPS = 0
(b) MPC + MPS < 1
(c) MPC + MPS = 1
(d) MPC + MPS > 1
Answer:
(c) MPC + MPS = 1

Question 35.
On which factor does Keynesian Theory of Employment depend ?
(a) Effective demand
(b) Supply
(c) Production efficiency
(d) None of these
Answer:
(a) Effective demand

Question 36.
Who is the writer of the book Traited Economic Politique ?
(a) Pigou
(b) J. B. Say
(c) J. M. Keynes
(d) Ricardo
Answer:
(b) J. B. Say

Question 37.
Increase in aggregate demand of equilibrium level of income and production causes increase in
(a) employment
(b) production
(c) income
(d) all of these
Answer:
(d) all of these

Question 38.
Which of the following is a reason of appearing surplus demand ?
(a) Increase in Public expenditure
(b) Increase in Money supply
(c) Fall in taxes
(d) All of these
Answer:
(d) All of these

Question 39.
Budget may include __________
(a) Revenue deficit
(b) Fiscal deficit
(c) Primary deficit
(d) All of these
Answer:
(d) All of these

Question 40.
Which items are included in Balance of Pay-ments ?
(a) Visible items
(b) Invisible items
(c) Capital transfers
(d) All of these
Answer:
(d) All of these

Question 41.
The main reason of operating the law of increasing return is __________
(a) size efficiency
(b) specialisation
(c) indivisibility
(d) all of these
Answer:
(c) indivisibility

Question 42.
Which of the following is the formula for measuring the elasticity of supply ? Q

Answer:
(c) \(\frac { Q }{ ∆P }\) × ∆P

Question 43.
NNPmp = ?
(a) GNPmp- Depreciation
(b) GNPmp +Depreciation
(c) GNPmp+ Indirect tax
(d) None of these
Answer:
(a) GNPmp- Depreciation

Question 44.
Who is the writer of the book “General Theory of Employment, Interest and Money” ?
(a) Pigou
(b) Malthus
(c) J.M. Keynes
(d) Marshall
Answer:
(c) J.M. Keynes

Question 46.
Keynesian multiplier principle establishes relationship between
(a) Investment and Income
(b) Income and Consumption
(c) Savings and Investment
(d) None of these
Answer:
(a) Investment and Income

Question 47.
Which of the following is the equilibrium condition for circular flow in four sector flow ?
(a) C + I
(b) C +1 + G
(c) C + 1 + G + (X- M)
(d) None of these
Answer:
(c) C + 1 + G + (X- M)

Question 48.
The sum of market prices of all final goods and services produced by the producers in the domestic territory of a country in an accounting year is known as
(a) GDPmp
(b) GDPfc
(c) NNPpc
(d) None of these
Answer:
(a) GDPmp

Question 49.
Which of the following is a real investment ?
(a) Purchasing of a share
(b) Purchasing of an old factory
(c) Construction of buildings
(d) Opening deposit account in the bank
Answer:
(c) Construction of buildings

Question 50.
The value of Keynesian Investment Multiplier depends on
(a) Income level
(b) Marginal productivity of capital
(c) Marginal propensity of consumer
(d) Investment level
Answer:
(d) Investment level

Non-Objective Type Questions

Short Answer Type Questions

Question no. 1 to 25 are Short answer type questions. Answer any 15 out of them. Each question carries 2 marks. (15 x 3 = 30)

Question 1.
Distinguish between Giffen goods and Inferior goods.
Answer:

1. Normal goods (Giffen goods) : Normal goods are those goods for which the demand rises with every increase in the income of consumer. In other words, in case of normal goods, there is a direct relationship between income of a consumer and his demand for normal goods e.g. the demand for rice and wheat will increase with very increase in income. Thus, rice and wheat are normal goods.
2. Inferior goods : Inferior goods are low quality products and their demand decrease when income of consumer increases and vise versa. In other words, in case of interior goods, there is an inverse relationship between demand and income of consumer e.g. the demand for pea nuts or bajra will full with the rise of the income of the consumer. Hence pea nuts and bajra become inferior goods at a higher level of income.

Question 2.
What is price elasticity of demand ? How is it measured ?
Answer:
Price elasticity of demand or elasticity of demand
According to Marshall,” The. elasticity (or responsiveness) of demand in a market is great or small according as the amount demanded increases much or little for a given fall in price, or diminishes much or little for a given rise in price.”

According to Samuelson.” This is a concept devised to indicate the degree of responsiveness of quantity demanded to changes in market prices.”
It is clear that:
“Price elasticity of demand may be defined as the percentage change in the quantity demanded of a commodity divided by the percentage change in price of that commodity.”

Elasticity of demand = \(\frac { Proportionate change in quantity demanded }{ Proportionate change in price. }\)

An online step by step percentage difference calculator.

Question 3.
What is Capital Adequacy Ratio Criteria ?
Answer:
Capital Adequacy Ratio Criteria : Capital adequacy ratio critieria applies for commerical bank. Under this scheme, it is compulsory to get 8% CAR for all banks working in India. All the public banks of country have got this capital adequacy ratio (CAR).

Question 4.
What is seasonal unemployment ?
Answer:
Seasonal Unemployment: Many of factories or industries work on seasonal basis. When working season on pick point they hire workers or they give employment and the other hand when season rise on pick off or-when season off they voluntary loose their workers or they spread unemployment this process is called seasonal unemployment.

Question 5.
What are deposits ?
Answer:
Deposit : It refers to those amount which accepted by banks and deposited by public for security of wealth and earning purpose. Banks take deposit from public and give a certain rate of interest.

Question 6.
Define Clearing house.
Answer:
By clearing house function of central bank we mean that, “Setting the claims of various banks against each other with least use of cash.”

Question 7.
What is progressive tax ?
Answer:
The Rate of tax decreases while income increases, in progressive system.

Question 8.
What is exchange rate ?
Answer:
Exchange rate expresses the ratio of exchange between the currencies of two countries. Hence, exchange rate is the price of a country expressed in terms of another currency.

Question 9.
Distinguish between inflationary and deflationary gap.
Answer:
“Inflationary gap is the measure of the amount by which aggregate demand exceeds the level of Aggregate demand required to maintain full employment.” “Deflationary gap, when difference occures between unsufficient supply and unsufficient demand is called deflationary gap.”

Question 10.
“Excess demand shows inflationary gap.” Clarify.
Answer:
Excess demand implies inflationary Gap : “Inflationary gap is the measure of the amount by which aggregate demand exceeds the level of aggregate demand required to maintain full employment equilibrium.”

In other words the difference between aggregate demand and aggregate supply is called inflationary gap. On situation of inflationary gap production in the economy dos not increase only prices rise i.e. at the point of full employment, production becomes constant and prices start rising. In inflationary pressure emerges in the economy.

Question 11.
What is the relationship between primary deposits and derived deposits ?
Answer:

1. Primary Deposits : Primary deposits refers to that deposit which is deposited in form of real money by banks.
2. Derived deposits : On the contrary when banks give loan to any person then that bank takes deposits of that loan in the account of that person in their own bank and deposited amount written by bank in that account is called derived deposits.

Question 12.
What is the role of bank rate in credit control ?
Answer:
The most important function of the central bank is to control the credit activities of commercial banks. Credit control refers to the increases or decrease in the value of credit money in accordance with the monetary requirement of the country. More expansion of credit money than necessary leads to the situation of inflation greater contraction of credit money on the other hand, might create a situation of deflation.

Question 13.
Explain the properties of money.
Answer:
Following are the merit or quality of good money :-

1. Utility :- The metal with which coin is made, must bear the feature of utility.
2. Portability :- The metal, with which coin is made, can easily be transferred from one place to another. Gold and silver coins bear this feature also.
3. Durable :- Money is saved by people and hence, coin should be made of such metal which is durable from saving purpose.
4. Divisibility:- Money metal should be divisible without any loss in its. Gold and silver are such metals having the feature of divisibility.
5. Homogeneity:- All units of money should be homogeneous.
6. Economy Minting cost of coin should be minimum and the depreciation in the coin should be least.
7. Stability of value Money metal should be stable in value i.e. price fluctuation in the metal of coin should be minimum.
8. Liquidity:- Money metal should be liquid in nature. Metal should easily be converted into coins and coins can be again be converted into metal easily.
9. Congnisibility :- Metal should easily be identified. Take coins can easily be traced out if metal of money is cognisible. Gold and silver are such metals having full congnisibility.

Question 14.
What is Budget ? Discuss Performance Budget and Gender Budget.
Answer:
Budget is a detailed economic statement which includes the details of income and expenditure of the government. According to Rene Stoum, “The budget is a document containing a preliminary approaval plan of public revenue and expenditure.”

1. Revenue budget : The revenue budet consists of revenue receipts of the governments and the expenditure met from rush revenues. The receipts includes tax revenue and non-tax revenue.
2. Capital budget: The capital budget consists of capital recepits and capital revenue of the Government.

Question 15.
Distinguish between fixed and flexible exchange rate.
Answer:
Difference between Fixed Exchange Rate and Flexible Exchange Rate are following :

1. Fixed Exchange Rate : The rate which is officially fixed in terms of gold or any other currency by the govt, such a rate does not vary with charges in demand and supply of foreign currency only the govt, has the power to charge it.
2. Flexible Exchange Rate : The rate which is determined by the forces of demand and supply of foreign exchange. There is an official intervention. It is free to flucted according to to changes in demand and supply of foreign currency.

Question 16.
What is balance of Trade ? Distinguish between current account and capital account in balance of payments.
Answer:
Balance of Trade : It is defined as the difference between exports and imports of goods. It takes into account only those transactions arising out of exports and import of roads. It does not consider the exchange of services between countries.
Symbolically, BoT = V_x – V_m
Where, V_x = Value of exports.
V_m = values of imports.
Current Account: Deposits in current account are payable on demand. They can be drawn of quench without any restriction. These accounts are usually maintained by business and are used for making business payments. No interest is paid on these deposits :
Capital Account : Capital account refers to those account which is maintained the capital of proprietor.

Question 17.
In an economy marginal propensity to consume is 0.65 and increase in investment is 90 crores of rupees. Calculate increase in total income and consumption expenditure.
Answer:
Multipler (k) = \(\frac { 1 }{ 1 – MPC }\)
= \(\frac { 1 }{ 1 – 0.65 }\) = \(\frac { 1 }{ 0.35 }\) = 5
MPS = 1 – MPC = 1 – 0.65 = 0.35
Increase in Income = K × 41
5 × 90 = rs. 45 Crores
Increase in consumption = 0.35 × 45 = 15.75 crores

Question 18.
What is the law of price elasticity of demand ?
Answer:
Law of demand

= \(\frac { Proportionate in demand community }{ Proportional change in Price }\)
Where, TR = Total Revenue
AR = Average Revenue
Q = Quantity.

Question 19.
What is cost function ?
Answer:
Cost functions expresses the relationship between production and cost function.

Question 20.
Explain the ‘micro’ and ‘macro’ levels of economic activity.
Answer:
Micro economics is concerned with an individual economic unit like a consumer,a firm ,an industry or income of an individual.lt is based on the assumption of full employment.Its central problem is price determination. What is true at micro level may not be true for macro level. lt is based on the assumption of ‘other things being equal.This analysis is based on partial equilibrium.Its objective is to study the theories related to optimum distribution of resources. Itsnature is comparatively easy. It has main instruments of demand and supply.

Macro economics deals with aggregates of economy such as national income,aggregate expenditure,tota lemployment,general price level,etc. lt is based on the assumption of under full employment of resources.Its central problem is production and employment determination.Group behaviour is applicable on entire economy.This is based on general equilibrium analysis.Its objective is to study the theories related with full employment.Its nature is comparatively complex.Its main instruments are aggregate demand .aggregate supply .aggregate saving and investment.

Question 21.
What is fiscal deficit? What are its effects?
Answer:
Fiscal deficit does not take into account all types of receipts. lt does not take into account borrowings.As such .fiscal deficit is defined as the excess of all expenditure over total receipts net of borrowings. In terms of formula,Fiscal deficit = Total budget expenditure – Total budget receipts net of borrowings.

For example,in the central government’s budget of 2002- 2003 total expenditure was Rs. 172 thousand crores while receipts other than planned borrowings were Rs.125 thousand crores.As such fiscal deficit was Rs.47 thousand crores (172- 125).Fiscal deficit indicates the total amount by which the government has to resort borrowing.
Its effects are as follows :

1. It helps in increasing the amount of capital expenditure in the economy.
2. Government can collect more resources for meeting out its expenditure
3. It may be lead to inflationary pressure in the economy.
4. High fiscal deficit generally leads to wasteful and unnecessary expenditure by the government. So, fiscal deficit should be kept as low as possible.
5. The entire amount of fiscal deficit i.e.borrowings is not available for meeting expenditure because a part of it is used for interest payment.

Question 22.
What is production function ?
Answer:
A Production function expresses the technical relationship between input and output of a firm. lt tells us about the maximum quantity of output that can be produced with any given quantities of inputs.If there are two factor inputs, labour (L) and capital (K),then production function can be written as: Q = f (L,K)
Where,
Q = Quantity of output
L = Units of labour
K = Units of capital
It may be pointed here that both the inputs are necessary for the production.If any of the inputs is zero,there will be no production with both inputs and output will also be zero, As we increase the amount of any one input,output increases.

Question 23.
State the features of monopoly.
Answer:
Monopoly is the addition of two words,i.e;’Mono’+’Poly’,i.e.,single seller in the market.Being the single seller in monopoly market,a firm has full control on the supply of the commodity.In pure monopoly even no close substitute of the product is available in the market.

In monopoly ,no distinction arises between ‘firm’ and ‘ industry i.e.,firm is industry and industry is firm. According to McConnell,’ ‘Pure monopoly exists when a single firm is the sole producer of a product for which there are no close substitutes.”

Question 24.
Discuss the functions of money.
Answer:
The functions of money are as follows :

1. Primary functions
2. Secondly functions and

(1) Primary functions : Money has two prime functions:

• Medium of exchange : Money acts as a medium of exchange.In modem days,exchange is the basis of entire economy and money makes this exchange possible.At present money is the most liquid means of exchange.In modem times,money performs all functions of exchange in the economy.
• Measure of value : Money acts a unit of measure of value.In other words,it acts as a yardstick of standard measure of value to which all other things can be measured.

(2) Second functions: There are three secondly functions are as follows:

• Standard of deferred payments : Deferred payments mean those payments which are future.Money performs this function successfully because it is more durable as compared to other commodities .
• Store of value : Human being has a tendency to save a part of his income for future to fulfill his future requirements.
• Transfer of value : Money is a liquid means of exchange. Hence,purchasing power of money can easily be transferred from one person to another or one place to the other.

Question 25.
What is gross domestic product?
Answer:
Gross domestic product (GDP)refers to the money value of all the final goods and services produced within the domestic territory of a country.GDP is a territorial concept as it confined to domestic territoiy of a country.lt does not include net factor earning from abroad. GNP = GDP +NFYA (NFYA indicates Net factor Income from Abroa (d) .GDP is a smaller concept limited to domestic territory.

Long Answer Type Questions

Question no. 26 to 33 are Long answer type questions. Answer any 4 of them. Each question carries 5 marks. (4×5 = 20)

Percentage Difference calculator is a free online tool to find the percent difference between two numbers.

Question 26.
What is elasticity of supply ? Explain two methods of its measurement.
Answer:
Elasticity of supply : Elasticity of supply is the measurement of quantitative change in supply due to change in price. In other words, price elasticity of supply is the proportionate change in supply consequent upon proportionate change in price. ,
According to Marshall, “Elasticity of supply refers to the change in quantity supplied of a commodity in response to change in its price.”
Elasticity of supply (es)

= \(\frac { Proportionate change in quantity supplied }{  Proportionate change in price }\)

Measurement of supply Elasticity :

(a) Proportionate Method or Percentage Method : According to this method, elasticity of supply, (es) is the ratio between ‘Percentage change in quantity supplied’ and ‘percentage change in price’ of the commodity,

es = \(\frac { Proportionate change in quantity supplied }{ Proportionate change in price }\)

= \(\frac { change in quantity supplied }{ change in price Initial quantity }\) = \(\frac { Change in price }{ Initial price }\)

(b) Geometric method : Supply elasticity can also be measured through point method or geometric method.

Question 27.
Explain important functions of a central bank.
Answer:
Functions of central Bank :

1. Monopoly in Note Issue: In modern times, central bank alone has the exclusive right to issue notes in every country of the world. The notes issued by the central bank are unlimited legal tender throughout the country.
2. Banker Agent and financial advisor to the government: Like general public government also needs various services and the central bank performs the same functions as banker to the government as a commercial bank provides to its customers.
3. Bank of Banks : It performs the functions of a banker to all other banks in the country. Central bank has almost the same relation with all other banks as a commercial bank has with its customers. Central bank keeps part of the cash balances of all commercial banks as deposit with a view to meeting liabities of these banks in times of crises. Due to this act of the central bank, it is also called custodian of cash reserves.
4. Lender of the last Resort: As banker to the bank, the central bank acts as the lender of the last resort. In other words, in case the commercial banks fail to meet their financial requirements from other words, Sources, they can, as a last resort, approach to the central bank for and advances. The central bank assists such bank through discounting of approved. Securities and bills of exchange.
5. Custodian of foreign Exchange Reserves : Central bank also acts as custodian of foreign exchange reserves. It is helpful in eliminating difficulties of balance of payments and in maintaining stable exchange rate. For mininising fluctuations in foreign exchange rate, central bank buys or sells foreign exchange in the market.
6. Function of Cleaning House : Central bank also performs the function of a cleaning house. By cleaning house function of central bank we mean settling the claims of various banks against each other with least use of cash.
7. Credit control: The most important functions of the central bank is to control the credit activities of the commercial banks. Credit control refers to the increase or decrease in the volume of credit money in accordance with the monetary requirement of the country. More expansion of credit money than necessary leads of the situation of inflation. Greater contraction of credit money, on the other land, might create a situation of deflation.
8. Development Related Functions : For promoting economic development, central bank performs following

functions:

1. It extends organised banking system and establishes new financial Institution.
2. It ensures sufficient money supply for development activities.
3. Adopts cheap money policy for Inducing investment.

Other Functions :

1. Collection of Statistics
2. Relations with International financial Institutions
3. (c) Survey of Banks.
4. Arranging seminars.

Question 28.
What is the principle of effective demand ?
Answer:
According to keynesian employment theory in short period, total production i.e. national income in capitalist economy depends on the level of employment because in short period other factors of production such as capital, technique, etc. remain constant. Employment level depends on effective demand. That level of aggregate demand at which it becomes equal to aggregate supply is called effective demand.

Question 29.
What is the function of money ?
Answer:
Function of Money :

1. Medium of exchange : Money acts as a medium of exchange. In modern days, exchange is the basis of entire economy and money makes this exchange possible. At present, money is the most liquid means of exchanges.
2. Measure of value : Money acts a unit of measure of value. In other words, it acts as a yardstick of standard measure of value of which all other things can be measured.
3. Store of. value : Human being has a tendency to save a part of his income for future to fulfil his future requirements. Store of value can take place only when person became confident to use his savings as per his requirements in future. Money has this merit because its utility is never lost.
4. Transfer of value : Money is a liquid means of exchange, Hence, purchasing power of money can easily be transferred from one person to another or one place
   to the other. Thus, in modem times has become the best means of transferring the value of money.
5. Basis of credit: In modem times credit has a vital role in the economy. At present credit is used as money on the basis of money, credit is issued, i.e., bank or financial institutions create credit on the basis of money. Thus, money is the basis of credit.
6. Basis of Distribution of social Income : In modern times production is done on collective basis in which various factors of production-land, labour, capital, organisation perform their assigned role.
7. Basis of maximum satisfaction and production : Money helps consumers in maximising theit satisfaction. A consumer maximises his satisfaction by equating the prices of each commodity with its marginal utility.
8. Guarantee of solvency : Money serves as a guarantee of solevency for an individual or institution for retaining its solevency, every individual or institution prefers to keep some money ready as cash deposits. Money deposits serve as a guarantee against money.
9. Bearer of option : Money serves as a bearer of option which implies that accumulating wealth in the form of money, we can change our decisions regarding the goods and services as and when the situation demands.

Question 30.
Explain Consumer’s equilibrium with the help of Indifference Curve Analysis.
Answer:
Hick and Hellen presented ‘indifference curve analysis as on alternative viewpoint of marshall’s utility Analysis.
Indifference curve analysis presents and ‘ordinal viewpoint’ in which behaviour of consumer is studied on the basis of ‘ordinal preferences. Indifference curve explains the consumer’s behaviour related with the combination of two goods and this consumer behaviour is explained with the help of’indifference schedule’ various combinations of two goods giving equal satisfaction to the consumer become the component of ‘indifference schedule’. When indifference schedule is represented on a graph paper we get indifference curve.

Consumer’s equilibrium in indifference curve analysis : A consumer obtains the state of equilibrium when he becomes successful in maximising his satisfaction by purchasing goods with his limited income and given prices of goods. The price line of the consumer is determined by his income and prices of the goods he becomes, with this given price line, a consumer tries to obtain the maximum possible indifference curve.

In difference curve analysis curve analysis there are two conditions of consumer’s equilibrium:

i.e. at the point of equilibrium, the marginal rate of substitution X and Y should be equal to the ratio of prices of goods X and goods Y.

For stable equilibrium indifference curve should be convex to the origin at the point of equilibrium, i.e.
MRSxy should be diminishing at the point of equilibrium.

In fig. at point K first conditions is getting fulfilled but this equilibrium is not stable because at the point K the MRS is increasing. In fig. point t is a point of equilibrium where MRS, is diminishing.

Question 31.
Define a commercial bank and discuss its functions.
Answer:
Commercial banks perform general banking functions. A commercial bank is an institution which deals with money and credit. lt accepts deposits from the public,makes the funds available to those who need them and helps in remittance of money from one place to another.

According to Banking Regulation Act,” Banking means the accepting for the purpose of lending and investment of deposits of money from the public,repayable on demand or otherwise, and withdrawable by cheque,draft,order or otherwise.”
Its functions are as follows :
(i) Accepting deposits : The prime function of the commercial bank is to accept deposits from bank.The various types of deposits accepts by the commercial bank are as follows:

1. Current Deposits: Deposits in current account are termed as current deposits. Such account are useful for traders who need money for daily transactions many times in a day.
2. Saving Deposits : Such accounts generally belong to the people having small savings and who do not require withdrawal of money many times.Interest rate in such accounts to low. such accounts promote capital formation.
3. Fixed Deposits : In fixed accounts,account is deposited for a certain fixed period(which may be 46 days or more).Depositor gets deposit receipt while depositing cash in such accounts.
4. Recurring account : Recurring deposits are certain type of fixed deposit. Depositor deposits a certain amount every month in this account.

(ii) Granting loans: The second important primary function of commercial banks is advancing of loans. After keeping certain cash reserves ,the banks lend their deposits to needy burrowers.

1. Cash Credit : In cash credit system,bank provides loans to the borrower against bonds or some other types of securities.Businessmen deposit securities with the bank.
2. Overdraft : Overdraft is permitted to those customers who have current account with the bank while cash credit can be granted to anyone.
3. Loans and advances
4. Discounting the bills of exchange
5. Investment in government securities

(iii) Credit creation :

Question 32.
Explain the kinds of exchange rate. How are fixed and flexible exchange rates different?
Answer:
Exchange rate is mainly of two types :

1. Fixed Exchange rate
2. Flexible Exchange rate

Fixed rate of exchange refers to that rate of exchange which is fixed by the government. lt generally does not change or the changes can take place within a fixed limit only.

Flexible Rate of Exchange is that rate which is determined by market forces.Change in flexible exchange  rate occur on account of change in market demand and supply. lt is also called floating exchange rate. Fixed Exchange rate is decided and declared by the government and it kept stable but Flexible Exchange rate is determined by demand and supply forces in international market.

In Fixed exchange rate, the central bank becomes ready to buy or sell its currencies at a fixed rate. In Flexible exchange rate is freely dependent on the working of foreign exchange market and the central bank has nothing to do with it. In fixed rate of exchange ,no fluctuation takes place but in flexible rate of exchange fluctuations appear.

Question 33.
Explain the different methods through which central bank controls credits.
Answer:
The different methods through which central bank controls credits are as follows :

1. Quantitative methods
2. Qualitative methods

1. Quantitative methods : It refers to those methods of credit control which are used by the central bank to influence the total volume of credit without regard for the purpose for which the credit is put.

1. Bank Rate : Bank rate policy is the indirect important method for controlling credit money. The Bank rate is the rate of which the central bank is prepared to discount the first class bills of exchanges and grant loans to commercial banks.
2. Open market operations : Open market operations affect the cash reserves of commercial banks.Consequently credit creation by commercial bank increases or decreases and money supply expands or contracts respectively.
3. Change in cash reserve ratio (CRR): Every commercial bank has to maintain a certain ratio of its deposits with the central bank.When the cash flow or credit is to be increased,cash reserve ratio is reduced and when the cash flow or credit is to reduced,cash reserve ratio is reduced.
4. Change in statutory liquidity ratio (SLR) : Every bank is required to maintain a fixed percentage of its in the form of cash or other liquid assets .called SLR.

2. Qualitative methods : This method is used by the central bank to regulate the flow of credit into particular directions of the economy.

1. Rationing of credit: Central bank is the lender of last resort. So, it can adopt the measure of credit rationing for credit control.
2. Regulation of consumer’s credit : In this method,the credit given to durable consumer goods is controlled.
3. Change in margin requirements : Marginal requirement is the difference between the current value of physical security offered for loans and the value of loans granted.
4. Direct action : Central bank can take direct action against any commercial bank if the latter do not follow central bank’s direction.

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BSEB Bihar Board Class 8 English Book Solutions Chapter 13 My Shadow

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Bihar Board Class 8 English My Shadow Text Book Questions and Answers

A. Warmer

My Shadow Poem Questions And Answers Bihar Board Question 1.
Have you ever seen your shadow ?
What do you notice about it ?
Answer:
Yes, I have seen my shadow many times. In light I see it. In dark, it disappears. Slanting light makes it taller, light coming from top makes my shadow smaller.

Class 8 English Chapter 13 Question Answer Bihar Board Question 2.
Is your shadow always of the same length on different times of the day ?
Answer:
No, it is not the same all the time. In early morning it is small, with the rising of the day it grows taller.and in noon it becomes very small. After the noon it again grows and in evening it is again smaller and at night it disappears at all.

B. Let’s Comprehend

B. 1. Think and Tell

B. 1. 1. Answer the following questions very briefly

Class 8 Bihar Board English Book Question 1.
What is the piniest thing about the speaker’s (poet’s) shadow ?
Answer:
The way he likes to grow.

Bihar Board Class 8 English Solution In Hindi Question 2.
What happened on morning before the sunrise ?
Answer:
The shadow was not any where.

Bihar Board Class 5 English Book Solution Question 3.
Does the speaker’s shadow always remain the same ?
Answer:
No.

B. 1. 2. State whether the following statements are “Tue’ or ‘False’.

My Shadow Question Answer Bihar Board Question 1.

1. The speaker’s shadow jumps after him when he jumps into his bed.
2. At times, the speaker’s shadow is taller than him.
3. The speaker’s shadow always follows him.
4. The speaker’s shadow was very active.

Answer:

1. True
2. True
3. True
4. True

B. 2. Think and Write

B. 2. 1. Answer the following questions briefly.

Bihar Board Class 8 English Book Solution Question 1.
What does the shadow of the speaker do ?
Answer:
The shadow goes in an out with the speaker.

Bihar Board Class 8 English Question 2.
How does the shadow grow ?
Answer:
The shadow grows the way he likes to.

Class 13 English Book Bihar Board Question 3.
Why does the speaker call his shadow lazy ?
Answer:
In early morning he doesn’t get up with him.

B. 2. 2. Answer the following questions in about 50 – 60 words.

Bihar Board Class 8 English Book Question 1.
How does the shadow of the speaker behave ? Does your shadow also behave similarly ?
Answer:
The speaker’s shadow behave very funnily. Sometimes it grows very slow. Sometimes, it grows very fast. Sometimes it does not grow at all.
Yes, its right. My shadow also behaves likewise the speaker’s.

Class 8 English Book Bihar Board Question 2.
Why does the speaker call his shadow ‘the funniest thing’?
Answer:
The speaker calls his shadow ‘the funniest thing’ because it likes to grow ifi its own way. Sometimes it shoots up taller like an India rubber ball. Sometimes it gets so little that there’s none of it could be seen.

My Shadow Solutions Bihar Board Question 3.
Why do you think that the shadow of the poet did not accompany him before the sunrise ? Explain.
Answer:
The shadow of a person grows according to the light. Before sunrise there is dark. In darkness the shadow can’t grow. So, the shadow of the poet did not accompany him before the sunrise.

Question 4.
What do you like most about the poem ?
Answer:
I like the presentation of the shadow in the poem. The way if grows taller and the way it grows, smaller and disappears at all, amuses me.

C. Word Study

Look at these words

• funny – funnier – funniest
• little – more – most
• shining – more
• shining – most shining

Fill in the blanks with suitable degree of adjectives:

1. slow, slower, _______
2. _____, earlier, ______
3. fast, ______, _______
4. lovely, _____, _______
5. beautiful, ______, _____

Answer:

1. slow, slower, slowest
2. early, earlier, earliest
3. fast, faster, fastest
4. lovely, lovelier, loveliest
5. beautiful, more beautiful, most beautiful

D. 1. Grammar

Prepositions:

Read the following sentences:

• There is some water in the bottle.
• He is fond of his daughter.
• He fell off the ladder.

In sentence I, the word in shows the relation between two things – water and bottle. In sentence 2. the word of shows the relation between the adjective fond and the noun daughter. In sentence 3, the word off shows the relation between the verb fell and the noun ladder.

These words which are used before a noun or a pronoun to show its relationship with another word in the sentence are called prepositions. The noun or pronoun which follows a preposition is called its object. Note that pronouns used after a preposition should be in the objective case.

He is fond of her. (NOT He is fond of she)

A preposition may have two or more objects; e.g., Between you and me there are few secrets. (Here the pro¬nouns you and me are the objects of the preposition between.)

Prepositions show various kind of relations. The most important among them are the following:

Place:

• She ran across the street.
• The boy fell among the thorns.
• We were at the foot of the hill.
• The thief was biding behind the cupboard.

Time:

• I have a meeting in the afternoon.
• You must return before sunset.
• Wait till tomorrow.
• We waited for hours

Method and manner:

• The letter came by post,
• He cut the cake with a knife.
• They fought with courage.
• They succeeded by hard work.

Reason and Purpose:

• She died of malaria.
• He trembled with anger.
• Smoking is injurious to health.

Possession:

• He is a man of principles,
• Mumbai is the financial capital of India.
• I saw a boy with red hair.

Direction and Motion:

• He fell into the well.
• He climbed up the tree.
• She walked towards the market.
• The moon moves ground the sun.

Prepositions – Time:

Other important Prepositions:

I. Write prepositions in the blanks.

1. The railway station is ___________ Hajipur Road, the ___________ river.
2. They live ___________ the same roof.
3. I have not set in ___________ last Wednesday.
4. I have known him ___________ a long time.
5. The robbers jumped ___________ the train while it was still moving.
6. Turn ___________ the light! I have to sleep.
7. This is a matter ___________ great importance.
8. He has not yet recovered ___________ his illness.
9. They were arguing ___________ who was the first one to see the tiger.
10. Please take ___________ your boots. They’re very dirty.
11. I put my hands ___________ my eyes because I couldn’t bear to see the crocodiles fight.
12. I took us ___________ ten minutes to finish the big bowl popcorn.
13. Is there a toilet ___________ there ?
14. We paddled quickly downstream as our boat was ___________ crocodiles and hippopotamuses.
15. He jumped out ___________ the car just before it fell ahill.
16. He took an hour to choose ___________ a white dress and a black dress.
17. They decided to take legal action ___________ him for driving the influence of alcohol.
18. ___________ six years, the hospital is still construction.
19. The lorry was moving ___________ full speed when the load of duck’s eggs fell
20. It won’t fall ___________ because I have twisted the wire that post to keep it position.
21. ___________ the 1990s. he lived alone an island the coast of Africa.
22. This week she has to work ___________ midnight Monday ___________ Friday.
23. Could 1 talk to you ___________ a few minutes ?
24. Her room is ___________ the corridor the left.
25. Police want to know’ all ___________ it and are calling for witnesses.
26. He blew ___________ the lamp and lay down the ground.
27. Suddenly, the tiger appeared ___________ him. I pounced ___________ him ___________ warning.
28. The force ___________ the spring threw him away ___________ the tiger, and he jumped his feet, ready ___________ face his enemy.
29. We have not met ___________ last October.
30. Books were scattered ___________ the room.
31. Fire-crackers are set ___________ to Trighten the evil spirits.
32. Luckily, the wind died down and the fire began to bum itself ___________
33. I lived in Delhi ___________ six years.
34. The referee ordered two players ___________ the field.

Answer:

1. The railway station is on Hajipur road, beside the river.
2. They live under the same roof.
3. I have not seen him since last Wednesday.
4. I have known him for a long time.
5. The robbers jumped off the train while it was still moving.
6. Turn of the light! I have to sleep.
7. This is a matter of great importance.
8. He has not yet recovered from his illness.
9. They are arguing about who was the first one to see the tiger.
10. 10. Please take off your boots. They’re very dirty.
11. I put my hands on my eyes because I couldn’t bear to see the crocodiles fight.
12. It took us about ten minutes to finish the big bowl of popcorn.
13. Is there a toilet over there ?
14. We paddled quickly down stream as our boat was before crocodiles and hippopotamus.
15. He jumped out off the car just before it fell down a hill.
16. He took an hour to choose between a white dress and a black dress
17. They decided to take legal action against him for driving in the influence of alcohol.
18. For six years, the hospital is still under construction.
19. The lorry was moving at full speed when the load of duck’s eggs fell off.
20. It won’t fall down because I have twisted the wire with that post to keep it within position.
21. In the 1990s, he lived alone on an island along the coast of Africa.
22. This week she has to work till midnight Monday to Friday.
23. Could I talk to you for a few minutes ?
24. Her room is by the corridor to the left.
25. Police want to know all about it and are calling for witnesses.
26. He blew off the lamp and lay down on the ground.
27. Suddenly, the tiger appeared before him. It pounced on him without warning.
28. The force of the spring threw him away towards the tiger, and he jumped at his feet, ready to face his enemy.
29. We have not met since last October.
30. Books were scattered around the room.
31. Fire-crackers are set to frighten the evil spirits.
32. Luckily, the wind died down and the fire began to bum it self down.
33. I lived in Delhi for six years.
34. The referee ordered two players out of the field

D. 2. Rhyme Time

Example:
Me in the poem rhymes with ‘see’. Pick out some other rhyming words from the poem.

Question 1.
Add two more rhyming words to the following:

1. heel, feel, ______, _______
2. lazy, hazy, ______, _______
3. sun, bun, ______, _______
4. shoot, boot, ______, _______
5. slow, blow, ______, _______
6. thin, ring, ______, _______
7. ball, hall, ______, _______
8. cup, up, ______, _______
9. bed, red, ______, _______
10. pick, lick, ______, _______

Answer:

1. heel, feel, kneel, reel
2. lazy, hazy, crazy, daisy
3. sun, bun, nun, ton
4. shoot, boot, hoot, jute
5. slow, blow, glow, flow
6. thing, ring, sing, king
7. ball, hall, call, mall
8. cup, up, pup, sup
9. bed, red, head, said
10. pick, lick, tick, chick

E. Let’s Talk

Question 1.
All of you should look at your shadow at different times of the day and note how different it looks ever time and why. Discuss whether your shadow behaves differently from the shadows of other.
Answer:
Prakash: Very early morning, our shadow its not seen when the sun is not up.
Neha: With the rise of the sun, our shadow grows taller.
Rakesh: In noon, the sun being at the top of our head our shadow is not seen.
Harsh: After the noon, till evening again our shadow grows taller.
Moni: After evening, with the fall of night, till morn again our shadow gets disappeared.

F. Composition

Question 1.
Write a paragraph oh ‘What I like and dislike about my shadow’ ?
Answer:
I like my shadow growing taller. I like my shadow going with me and following me. I like to play with my shadow. I like to run and a muse with it. When my shadow is very taller than me I don’t like it. I also don’t like my shadow going between my heels. And the most annoying thing about my shadow that I dislike is, when my shadow disappears at all at night.

G. Translation

Question 1.
Translate the following into English
मुझे प्रकाश में अपनी परछाई दिखती है। जब मैं चलता हूँ वह भी चलती है। जब मैं रूकता हूँ वह भी रूकती है। परन्तु वह अंधेरे में छिप जाती है। कभी वह बहुत लम्बी होती है और कभी वह बहुत छोटी हो जाती है। उसका रहस्य मुझे समझ में नहीं आता है।
Answer:
In light, my shadows is seen. When I walk, she also walks with me. When I stop, she also stops. But in dark she hides away. Sometimes she is very tall and sometimes she becomes very short. I can’t understand her secret.

H. Activity

Question 1.
Moving a light source closer to an object can make its shadow grow larger while moving the light source away can have the opposite effect. Experiment and see what happens to the shadows of different objects when you tilt the light source or change its brightness, what happens to the shadow if you make the light source very dim ?
Answer:
In dim light our shadow can’t be seen. Do the experiment yourselves.

Question 2.
See how sunlight creates shadows with various objects such as trees, houses and cars. Learn how the sun’s position in the sky affects the size of shadows.
Answer:
When the sun rays is slanting, the shadows of different objects grow longer. And when the sun is at the top straight, the shadows of objects go smallers.

My Shadow Summary in English

‘My Shadow’ is a entertaining poem. The poem is Penned by the poet, Robert Louis Stevenson. The speaker of the poem is a child. The child is wondering about his shadow. The shadow keeps on changing. Sometimes it shoots up, grows up taller than him. Sometimes it becomes very little and vanishes too. This surprises the speaker. He makes a search for his shadow and explains it.

My Shadow Summary in Hindi

‘माई शैडो’ (मेरी परछाई) एक मनोरंजक कविता है। प्रस्तुत कविता के कवि हैं रॉबर्ट लुईस स्टीवेन्सन । कविता का वक्ता एक बालक है। वह बालक अपनी परछाईं को लेकर आश्चर्य में पड़ा रहता है। उसकी परछाईं बार-बार बदलती रहती है। कभी तो वह उससे भी बड़ी हो जाती है और कभी तो वह अत्यंत छोटी हो जाती है और कभी तो एकदम से गायब हो जाती है। यह बात वक्ता को आश्चर्य में डाल देती है। वह अपनी छाया की तलाश करत है, उसके बारे में जानकारी इकट्ठा करता है और सबको बताता है।

My Shadow Hindi Translation of The Chapter

Shadow (n) [शैडो] = परछाईं, छाया। Use (n) [यूज] = व्यवहार, प्रयोग । More (adj) [मोर] = अधिक, ज्यादा । Very (adj) [वेरी] = बहुत । Like (adj) [लाइक] = जैसा, समान । Heels up (phr) [हील्स अप] = ऊपर की ओर उठता है। Jump (v) [जम्प] = उछलना । Funniest (adj) [फनीएस्ट] = सबसे मजेदार । मजा किया। Way (n) [वे] = तरीका । Proper (adj)[प्रॉपर] = उचित, योग्य । Always (adv) [ऑलवेज) = सदा, हमेशा । Shoots up (phr) [शूट्स अप] = आगे को बढ़ जाता है। Indian rubber ball (n) [इण्डियन रबड़ बॉल] = उछलने वाली भारतीय गेंद । Early (adj) [अर्ली] = सवेरे । Rose (v)[रोज] = जगा, उठा । Found (v) (फाउन्ड] = पाया । Shining (adj)[शाइनिंग] = चमकता हुआ। Dew (n) [ड्यू] = ओस | Buttercup (n) [बटर कप] = एक प्रकार का पीला फूल । Arrant (adj) [एरेन्ट] = बुरा । Sleep (adj) [स्लीप] = निद्राग्रस्त, सोया हुआ-सा । Fast asleep (phr) [फास्ट अस्लीप] = गहरी नींद में सोया हुआ।

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