8A) Environment Ecology (Prelims PYQs)

1] “If rainforests and tropical’ forests are the lungs of the Earth, then surely. ‘wetlands function as its kidneys.” Which one of the following functions of wetlands best reflects the above statement? [2022]

a) The water cycle in wetlands involves surface runoff, subsoil percolation and evaporation.
b) Algae form the nutrient base upon which fish, crustaceans, molluscs, birds, reptiles and mammals thrive.
c) Wetlands play a vital role in maintaining sedimentation balance and soil stabilization..
d) Aquatic plants absorb heavy metals and excess nutrients.

2] Consider the following kinds of organisms: [2021]
1) Copepods
2) Cyanobacteria
3) Diatoms
4) Foraminifera
Which of the above are primary producers in the food chains of oceans?

a) 1 and 2
b) 2 and 3
c) 3 and 4
d) 1 and 4

3] In case of which one of the following biogeochemical cycles the weathering of rocks is the main source of release of nutrient to enter the cycle? [2021]

a) Carbon cycle
b) Nitrogen cycle
c) Phosphorus cycle
d) Sulphur cycle

4] Which of the following are detritivores? [2021]
1) Earthworms
2) Jellyfish
3) Millipedes
4) Seahorses
5) Woodlice
Select the correct answer using the code given below.

a) 1, 2 & 4 only
b) 2, 3, 4 & 5 only
c) 1, 3 & 5 only
d) 1, 2, 3, 4 & 5

5] Which of the following have species that can establish symbiotic relationship with other organisms? [2021]
1) Cnidarians
2) Fungi
3) Protozoa
Select the correct answer using the code given below.

a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

6] Consider the following statements: [2019]
1. Some species of turtles are herbivores.
2. Some species of fish are herbivores.
3. Some species of marine mammals are herbivores.
4. Some species of snakes are viviparous.
Which of the statements given above is/are correct?

a) 1 and 3 only
b) 2, 3 and 4 only
c) 2 and 4 only
d) 1, 2, 3 and 4

7] Which of the following leaf modifications occur(s) in the desert areas to inhibit water loss? [2018]
1. Hard and waxy leaves
2. Tiny leaves
3. Thorns instead of leaves
Select the correct answer using the code given below:

a) 2 and 3 only
b) 2 only
c) 3 only
d) 1, 2 and 3

8] Due to some reasons, if there is a huge fall in the population of species of butterflies, what could be its likely consequence/consequences? [2017]
1. Pollination of some plants could be adversely affected.
2. There could be a drastic increase in the fungal infections of some cultivated plants.
3. It could lead to a fall in the population of some species of wasps, spiders and birds.
Select the correct answer using the code given below:

a) 1 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

9] Which one of the following is the best description of the term ‘ecosystem’? [2015]

a) A community of organisms interacting with one another
b) That part of the Earth which is inhabited by living organisms
c) A community of organisms together with the environment in which they live.
d) The flora and fauna of a geographical area.

10] Lichens, which are capable of initiating ecological succession even on a bare rock, are actually a symbiotic association of: [2014]

a) Algae and bacteria
b) Algae and fungi
c) Bacteria and fungi
d) Fungi and mosses

11] Which one of the following is the correct sequence of a food chain? [2014]

a) Diatoms-Crustaceans-Herrings
b) Crustaceans-Diatoms-Herrings
c) Diatoms-Herrings-Crustaceans
d) Crustaceans-Herrings-Diatoms

12] Which of the following adds/ads carbon dioxide to the carbon cycle on the planet Earth? [2014]
1. Volcanic action
2. Respiration
3. Photosynthesis
4. Decay of organic matter
Select the correct answer using the code given below.

a) 1 and 3 only
b) 2 only
c) 1, 2 and 4 only
d) 1, 2, 3 and 4

13] Which of the following leaf modifications occurs/occur in desert areas to inhibit water loss? [2013]
1. Hard and waxy leaves
2. Tiny leaves or no leaves
3. Thorns instead of leaves
Select the correct answer using the codes given below.

a) 1 and 2 only
b) 2 only
c) 1 and 3 only
d) 1, 2 and 3

14] With reference to food chains in ecosystems, consider the following statements: [2013]
1. A food chain illustrates the order in which a chain of organisms feed upon each other.
2. Food chains are found within the population of a species.
3. A food chain illustrates the numbers of each organism which are eaten by others.
Which of the statements given above is/are correct?

a) 1 only
b) 1 and 2 only
c) 1, 2 and 3
d) None

15] Which of the following adds/ adds nitrogen to the soil? [2013]
1. Excretion of Urea by animals
2. Burning of coal by man
3. Death of vegetation
Select the correct answer using the codes given below.

a) 1 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2, and 3

16] 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? [2013]

a) Ecotone
b) Ecological niche
c) Habitat
d) Home range

17] In the grasslands, trees do not replace the grasses as a part of an ecological succession because of___? [2013]

a) Insects and fungi
b) Limited sunlight and paucity of nutrients
c) Water limits and fire
d) None of the above

18] Which one of the following is the correct sequence of ecosystems in the order of decreasing productivity? [2013]

a) Oceans, lakes, grasslands, mangroves
b) Mangroves, oceans, grasslands, lakes
c) Mangroves, grasslands, lakes, oceans
d) Oceans, mangroves, lakes, grasslands

19] With reference to the food chains in Ecosystems which of the following kinds of organism, is/are known as decomposer organism/ organisms? [2013]
1. Virus
2. Fungi
3. Bacteria
Select the correct answer using the codes given below.

a) 1 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

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