AIIMS Biology Ecosystem Class 12 Questions

Read the Assertion and Reason carefully to mark the correct option from those given below Assertion Gross primary productivity is always more than net primary productivity. Reason Consumers exhibit secondary productivity in a ecosystem.

In each of the following questions statement of Assertion is given followed by corresponding statement of Reason. Of the statements, mark the correct answer as Assertion (A) The rate of decomposition of detritus is reduced in the regions of high altitude. Reason (R) It happen due to immobilisation of nutrients.

Assertion : Some marine animals find it difficult to live in fresh water and vice versa. Reason : Some animals can tolerate a narrow salinity range, while others can tolerate a wide salinity range.

Assertion: In a terrestrial ecosystem, detritus food chain is the major conduit for energy flow. Reason: Solar energy is the direct source for energy supply in a detritus food chain.

Assertion: A network of food chains existing together in an ecosystem is known as a food web. Reason: An animal like kite cannot be a part of a food web.

Given below is one of the types of ecological pyramids. This type represents

The Great Barrier Reef along the east coast of Australia can be categorised as

Mr. X is eating curd/yoghurt. For this food intake in a food chain he should be considered as occupying:

Assertion : In a food chain members of successive higher levels are fewer in number. Reason : Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level.

The sphere of living matter together with water, air and soil on the surface of earth is called:-