Q. 1. Biodiversity forms the basis for human existence in the following ways
1. Soil formation
2. Prevention of soil erosion
3. Recycling of waste
4. Pollination of crops
(a) 1, 2 and 3 only
(b) 2, 3 and 4 only
(c) 2 and 3 only
(d) 1, 2, 3 and 4
Ans. (d)
Explanation:
Biological diversity helps in the formation and
maintenance of soil structure and the retention of
moisture and nutrient levels. Biodiversity supports
ecosystem services including air quality, climate
water purification, pollination, and prevention of erosion.
Q. 2. The formation of ozone hole in the Antarctic region has been a cause, of concern.
What could be the reason for the formation of this hole?
(a) Presence of prominent tropospheric turbulence; and inflow of chlorofluorocarbons
(b) Presence of prominent polar front and stratospheric clouds; and inflow of
chlorofluorocarbons
(c) Absence of polar front and stratospheric clouds; and inflow of methane and
chlorofluorocarbons.
(d) Increased temperature at polar region due to global warming
Ans.(b)
Explanation:
The Nitric acid in polar stratospheric clouds reacts with CFCs to form chlorine, which
catalyses the photochemical distruction of ozone.
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Q. 3. Regarding “carbon credits”, which one of the following statements is not correct?
(a) The carbon credit system was ratified in conjunction with the Kyoto Protocol
(b) Carbon credits are awarded to countries or groups that have reduced greenhouse gases
below their emission quota
(c) The goal of the carbon credit system is to limit the increase of carbon dioxide emission
(d) Carbon credits are traded at a price fixed from time to time by the United Nations
Environment Programme
Ans. (d)
Explanation:
Under the Kyoto protocol, the caps or quotas for GHGs for the developed Annex 1 countries
are known as Assigned Amounts and are listed in Annex B.
The quantity of the initial Assigned Amount is demonited in individual units called assigned
amount units.
Q. 4. There is a concern over the increase in harmful algal blooms in the seawaters of India.
What could be the causative factors for this phenomenon?
1. Discharge of nutrients from the estuaries.
2. Run-off from the land during the monsoon.
3. Upwelling in the seas.
Select the correct answer from the codes given below:
(a) 1 and 3
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Ans. (d)
Explanation:
All the three processes help in bringing nutrients to the sea surface which promotes algal
growth.
Q. 5. A sandy and saline area is the natural habitat of an Indian animal species. The animal
has no predators in that area but its existence is threatened due to the destruction of its
habitat. Which one of the following could be that animal?
(a) Indian wild buffalo
(b) Indian wild ass
(c) Indian wild boar
(d) Indian gazelle
Ans. (b)
Explanation:
Indian wild ass is actually a threatened species available in the Rann of Kutch which is
saline and sandy.
Q. 6. The “Red Data Books” published by the International Union for Conservation of Nature
and Natural Resources (IUCN) contain lists of
1. Endemic plant and animal species present in the biodiversity hotspots.
2. Threatened plant and animal species.
3. Protected sites for conservation of nature and natural resources in various countries.
Select the correct answer using the codes given below;
(a) 1 and 3
(b) 2 only
(c) 2 and 3
(d) 3 only
Ans. (b)
Explanation:
Red Data Books species are classified into different categories of perceived risk.
Each Red Data Book usually deals with a specific group of animals or plants (e.g.reptiles,
insects or mosses).
The original IUCN Red Data Book threat categories have been widely applied to hundreds of
thousands of taxa of animals, plants and fungi.
Note that these categories refer to the conservation status of an organism in the wild, not to
its presence in cultivation or captivity.
Q. 7. Three of the following criteria have contributed to the recognition of Western Ghats-Sri
Lanka and Indo-Burma regions as hotspots of biodiversity:
1. Species richness
2. Vegetation density
3. Endemism
4. Ethno-botanical importance
5. Threat perception
6. Adaptation of flora and fauna to warm and humid conditions
Which three of the above are correct criteria in this context?
(a) 1, 2 and 6
(b) 2, 4 and 6
(c) 1, 3 and 5
(d) 3, 4 and 6
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Ans. (c)
Explanation:
To qualify as a hotspot, a region must meet 2 strict criteria;
1. It must contain atleast 1500 species of vascular plants as endemics, and
2. It has to have lost atleast 70% of its original habitat.
So we choose species richness as well as endemism.
Along with this threat perception is also necessary.
Q. 8. Human activities in the recent past have caused the increased concentration of carbon
dioxide in the atmosphere, but a lot of it does not remain in the lower atmosphere because of
1. its escape into the outer stratosphere.
2. the photosynthesis by phytoplankton in the oceans
3. the trapping of air in the polar ice caps.
Which of the statements given above is/ are correct?
(a) 1 and 2
(b) 2 only
(c) 2 and 3
(d) 3 only
Ans. (c)
Explanation:
Since CO2 is havier then air, it sinks in the ocean rather than moving up.
Also, during winter it is observed that CO2 is trapped in ice caps.
Q. 9. In the context of ecosystem productivity, marine upwelling zones are important as they
increase the marine productivity by bringing the
1. decomposer microorganisms to the surface.
2. nutrients to the surface.
3. bottom-dwelling organisms to the surface.
Which of the statements given above is/are correct?
(a) 1 and 2
(b) 2 only
(c) 2 and 3
(d) 3 only
Ans. (c)
Explanation:
Option C is correct. Upwelling is a process in which deep, cold and usually nutrient rich
water towards the ocean surface.
Q.10. With reference to India, consider the following Central Acts:
1. Import and Export (Control) Act, 1947
2. Mining and Mineral Development (Regulation) Act, 1957
3. Customs Act, 1962
4. Indian Forest Act, 1927
Which of the above Acts have relevance to/bearing on the biodiversity conservation in the
country?
(a) 1 and 3 only
(b) 2, 3 and 4 only
(c) 1, 2, 3 and 4
(d) None of the above Acts
Ans. (c)
Explanation:
All four facts are related to biodiversity, Import and Export of GMOs or exotic species is
prohibited whereas certain medicinal plants are subjected to high custom duties to regulate
their trade.
Mines regulation and forest conservation anyway involve provisions related to biodiversity
conservation.
Q. 11. Consider the following:
1. Photosynthesis
2. Respiration
3. Decay of organic matter
4. volcanic action
Which of the above add carbon dioxide to the carbon cycle on Earth?
(a) 1 and 4 only
(b) 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Ans. (c)
Explanation:
Photosynthesis by plants removes about 120 billion tons of carbon from the air per year, but
plant decomposition returns about the same amount.
When the oraganic matter is oxidized through respiration. It releases CO2 in atmosphere.
Also various volcanic eruptions and metamorphism release gases in the atmosphere.
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