Bihar Board 12th Biology Objective Important Questions Part 5
Question 1.
Moya’ and ‘Ratna’ are the varieties of:
(a) Rice
(b) Maize
(c) Wheat
(d) Bajra
Answer:
(a) Rice
Question 2.
Amensalism is an association between two species where:
(a) One species is harmed and other is benefitted
(b) One species is harmed and other is unaffected
(c) One species is benefitted and other is harmed
(d) Both the species are harmed
Answer:
(c) One species is benefitted and other is harmed
Question 3.
Maximum growth rate occurs in:
(a) Lag phase
(b) Senescent phase
(c) Exponential phase
(d) Stationary phase
Answer:
(c) Exponential phase
Question 4.
Mycorrhiza show:
(a) Commensalism
(b) Amensaiism
(c) Parasitism
(d) Mutualism
Answer:
(d) Mutualism
Question 5.
Aerosols reduce primary productivity by:
(a) Decreasing O2 concentration in atmosphere
(b) Reducing photosynthesis
(c) Competing with CO2
(d) Being toxic to chloroplast
Answer:
(b) Reducing photosynthesis
Question 6.
Project tiger has started in India in:
(a) 1973
(b) 1985
(c) 1981
(d) 1986
Answer:
(a) 1973
Question 7.
Which of these is caused by a retrovirus?
(a) Gonorrhoea
(b) AIDS
(c) Syphilis
(d) Trichomoniasis
Answer:
(b) AIDS
Question 8.
Which one of the following has largest population in a food chain.
(a) Producers
(b) Primary Consumers
(c) Secondary Consumers
(d) Decomposers
Answer:
(a) Producers
Question 9.
‘AIDS’ is caused by:
(a) Phage virus
(b) Papiloma virus
(c) Gemini virus
(d) Retro virus
Answer:
(d) Retro virus
Question 10.
Malaria is caused by:
(a) Giardia
(b) Mycoplasma
(c) Plasmodium
(d) Salmonella
Answer:
(c) Plasmodium
Question 11.
What is the main contribution of Neo-Darwinians to the theory of Darwinism?
(a) explanation of source of variation
(b) explanation of natural selection
(c) explanation of species formation
(d) explanation of isolation
Answer:
(a) explanation of source of variation
Question 12.
Syndrome means:
(a) Diseased condition
(b) Virulency of pathogen
(c) Malignancy
(d) a group of symptoms
Answer:
(d) a group of symptoms
Question 13.
Heterozygous organism for two shall be:
(a) RRyy
(b) RrYY
(c) RrYy
(d) RRYy
Answer:
(c) RrYy
Question 14.
Crossing over takes place during:
(a) Zygotene
(b) Pachytene
(c) Diplotene
(d) Leptotene
Answer:
(b) Pachytene
Question 15.
Longitudinal binary fission is found in:
(a) Amoeba
(b) Paramecium
(c) Euglena
(d) None
Answer:
(c) Euglena
Question 16.
The flippers of penguin and dolphin show:
(a) homology
(b) Analogy
(c) both
(d) None
Answer:
(b) Analogy
Question 17.
Spermatid transforms into following number of sperms:
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(a) 2
Question 18.
The chromosome number is Doun’s syndrome is:
(a) 48
(b) 47
(c) 49
(d) 46
Answer:
(b) 47
Question 19.
Followering is the basal part of ovule:
(a) Chalaza
(b) Hilum
(c) Nucellus
(d) None
Answer:
(b) Hilum
Question 20.
Which one of the following is a sexually transmitted disease?
(a) Typhoid
(b) Syphilis
(c) Cholera
(d) Malecia
Answer:
(b) Syphilis
Question 21.
Which is not greenhouse gases?
(a) Methane
(b) CO2 (CO2)
(c) chlorofluorocarbon
(d) Nitrogen
Answer:
(d) Nitrogen
Question 22.
Termination codon is:
(a) UGG
(b) GUG
(C) UAG
(d) AvG
Answer:
(C) UAG
Question 23.
Eutrophication causes decrease in:
(a) Dissolved hydrogen
(b) Dissolved salts
(c) Dissolved oxygen
(d) All of these
Answer:
(c) Dissolved oxygen
Question 24.
Which RNA is used as aminoacid acceptor?
(a) m RNA (m RNA)
(b) t RNA (t RNA)
(c) hn RNA (hn RNA)
(d) r RNA (r RNA)
Answer:
(b) t RNA (t RNA)
Question 25.
PCR method is useful for:
(a) DNA synthesis
(b) DNA amplification
(c) Protein synthesis
(d) Amino acid synthesis
Answer:
(b) DNA amplification
Question 26.
Anthesis is a phenomenon which refers to:
(a) growth of pollen tube inside ovary
(b) Formation of Pollen
(c) Opening of flower bud
(d) Development of anther
Answer:
(c) Opening of flower bud
Question 27.
When breeding is between animals of the same breed it is called:
(a) Inbreeding
(b) Out breeding
(c) Out crossing
(d) Cross breeding
Answer:
(a) Inbreeding
Question 28.
Ornithophily is pollination by:
(a) Man
(b) Wind
(c) Birds
(d) Bats
Answer:
(c) Birds
Question 29.
Baker’s yeast is:
(a) S. Cerevisae
(b) S. Ludwingi
(c) S. Octosporus
(d) Shizo saaharomyces
Answer:
(a) S. Cerevisae
Question 30.
Group of bacteria used in biogas production is:
(a) Eubacteria
(b) Organotroph
(c) Methanotroph
(d) Methanogen
Answer:
(d) Methanogen
Question 31.
Which are of the following works as biofertilizer in paddy field?
(a) blue-green algae
(b) yeast
(c) fungi
(d) insect pest
Answer:
(a) blue-green algae
Question 32.
Cancer of epithelial tissue is called:
(a) Lymphoma
(b) Liposa
(c) Leukaemia
(d) Cacinoma
Answer:
(d) Cacinoma
Question 33.
Which one of the following is oviparous?
(a) Flowering plants
(b) Crocodile
(c) Woman
(d) Monkey
Answer:
(b) Crocodile
Question 34.
Seeds of fruits are transformed:
(a) Corolla
(b) Style
(c) Wall of avary
(d) Ovule
Answer:
(d) Ovule
Question 35.
Dudhwa National Park is situated in:
(a) Assam
(b) U.P.
(c) Gujarat
(d) West Bengal
Answer:
(b) U.P.
Question 36.
Replication of DNA needs:
(a) DNA Ligase
(b) DNA Polymerase
(c) DNA Polymerase and DNA Ligase
(d) Translocase and RNA Polymerase
Answer:
(c) DNA Polymerase and DNA Ligase
Question 37.
What is the position of a tiger in food chain in shown below?
(Grass → Deer → Tiger):
(a) Producer
(b) Primary Consumer
(c) Secondary Consumer
(d) Decomposer
Answer:
(c) Secondary Consumer
Question 38.
Select the statement which explains parasitism best.
(a) One organism is benefited
(b) Both the organisms are benefitted
(c) One organism is benefitted, other is not affected
(d) One organism is benefitted, other is affected.
Answer:
(d) One organism is benefitted, other is affected.
Question 39.
The second trophic level in a lake is:
(a) phytoplankton
(b) Zooplankton
(c) Benthos
(d) Fishes
Answer:
(b) Zooplankton
Question 40.
The chromosomal constitution of Klinefelter’s syndrome is:
(a) 2A + XY
(b) 2A + XO
(c) 2A + XX
(d) 2A + XXY
Answer:
(d) 2A + XXY
Question 41.
Genes which have similar genotypic effect when present separately but together interact to produce a different trait & a ratio of 9 : 7 in F2 generation are known as:
(a) Supplementary genes
(b) Complementary genes
(c) Inhibitory genes
(d) Duplicate genes
Answer:
(b) Complementary genes
Question 42.
The fact that DNA is a helix of uniform diameter was found out by:
(a) Watson & Crick
(b) Franklin
(c) Hargovind Khorana
(d) Altenburg
Answer:
(b) Franklin
Question 43.
Mycorrhiza is the example of:
(a) Mutualism
(b) Commensalism
(c) Parasitism
(d) All
Answer:
(a) Mutualism
Question 44.
The initiation codon in Translation process is:
(a) GUA
(b) AUG
(c) UGA
(d) All
Answer:
(b) AUG
Question 45.
Archaeopteryx is the connecting link between:
(a) amphibia and reptile
(b) reptile and aves
(c) Aves and mammals
(d) None
Answer:
(b) reptile and aves
Question 46.
Pyrimidine is:
(a) Adenine
(b) Guanine
(c) Uracil
(d) All
Answer:
(c) Uracil
Question 47.
Couper’s glands are found in:
(a) Human male
(b) Human female
(c) Frog
(d) Snake
Answer:
(a) Human male
Question 48.
Polar bodies are formed during:
(a) Oogenesis
(b) Spermatogenesis
(c) Gametogenesis
(d) Spermiogenesis
Answer:
(a) Oogenesis
Question 49.
Which of the following theories explain evolution on the basis of changes in gene-frequency:
(a) Neo-Lamarckism
(b) Neo-Darwinism
(c) Synthetic theory
(d) Darwinism
Answer:
(c) Synthetic theory
Question 50.
An ecosystem does not alter because it is in a state of:
(a) Homeostasis
(b) Imbalance
(c) Deficient light
(d) Deficient components
Answer:
(a) Homeostasis