Our environment practice Questions

Which one of the following is an artificial ecosystem?

• (a) Pond

• (b) Crop field

• (c) Lake

• (d) Forest

In a food chain, the third trophic level is always occupied by

• (a) carnivores

• (b) herbivores

• (c) decomposers

• (d) producers

An ecosystem includes

• (a) all living organisms

• (b) non-living objects s

• (c) both living organisms and non-living objects

• (d) sometimes living organisms and sometimes non-living object

In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level? Grass → Grasshopper → Frog → Snake → Hawk

• (a) 5 k J

• (b) 50 k J

• (c) 500 k J

• (d) 5000 k J

Accumulation of non-biodegradable pesticides in the food chain in increasing amount at each higher trophic level is known as

• (a) eutrophication

• (b) pollution

• (c) biomagnification

• (d) accumulation

Depletion of ozone is mainly due to

• (a) chlorofluorocarbon compounds

• (b) carbon monoxide

• (c) methane

• (d) pesticides

Organisms which synthesise carbohydrates from inorganic compounds using radiant energy are called

• (a) decomposers

• (b) producers

• (c) herbivores

• (d) carnivores

In an ecosystem, the 10% of energy available for transfer from one trophic level to the next is in the form of

• (a) heat energy

• (b) light energy

• (c) chemical energy

• (d) mechanical energy

Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the

• (a) food web

• (b) ecological pyramid

• (c) ecosystem

• (d) food chain

Flow of energy in an ecosystem is always

• (a) unidirectional

• (b) bidirectional

• c) multi directional

• (d) no specific direction