NATURAL SCIENCE > BOTANY
1) Mycorrhizal biotechnology has been used in rehabilitating degraded sites because mycorrhiza enables the plants to
1) resist drought and increase absorptive area
2) tolerate extremes of pH
3) resist disease infestation
4) -
A) 1 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 1, 2 and 3


2) Which of the following leaf modifications occurs/occur in desert areas to inhibit water loss?
1) Hard and waxy leaves
2) Tiny leaves or no leaves
3) Thorns instead of leaves
4) -
A) 1 and 2 only
B) 2 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 1, 2 and 3


3) Which of the following statements is /are correct?
1) Viruses lack enzymes necessary for the generation of energy
2) Viruses can be cultured in any synthetic medium
3) Viruses are transmitted from one organism to another by biological vectors only
4) -
A) 1 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 1 only


4) With reference to the food chains in ecosystems, which of the following kinds of organism is/are known as decomposer organism/organisms?
1) virus
2) Fungi
3) bacteria
4) -
A) 1 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 2 and 3 only


5) Which one of the following terms describes not only the physical space occupied by an organism, but also its functional role in the community of organisms?
A) EcotoneB) Ecological niche
C) HabitatD) Home range
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Answer : Ecological niche


6) Which of the following adds/add nitrogen to the soil?
1) Excretion of urea by animals
2) Burning of coal by man
3) Death of vegetation
4) -
A) 1 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 1 and 3 only


7) Consider the following organisms : Which of the above is/are used as biofertilizer/biofertilizers?
1) Agaricus
2) Nostoc
3) Spirogyra
4) -
A) 1 and 2
B) 2 only
C) 2 and 3
D) 3 only
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Answer : 2 only


8) Improper handling and storage of cereal grains and oilseeds result in the production of toxins known as aflatoxins which are not generally destroyed by normal cooking process. Aflatoxins are produced by
A) bacteriaB) protozoa
C) mouldsD) viruses
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Answer : moulds


9) In the grasslands, trees do not replace the grasses as a part of an ecological succession because of
A) insects and fungiB) limited sunlight and paucity of nutrients
C) water limits and fireD) None of the above
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Answer : water limits and fire


10) With reference to the usefulness of the by-products of sugar industry, which of the following statements is /are correct?
1) Bagasse can be used as biomass fuel for the generation of energy.
2) Molasses can be used as one of the feedstocks for the production of synthetic chemical fertilizers.
3) Molasses can be used for the production of ethanol.
4) -
A) 1 only
B) 2 and 3 only
C) 1 and 3 only
D) 1,2 and 3
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Answer : 1 and 3 only