Assertion Reason Test: Ecosystem - NEET MCQ

A: Ecological pyramids cannot explain all the vital functions of any ecosystem.

R: Pyramids actually do not explain the role of organisms working at more than one trophic

level.

A: The successive process starts only in those areas, where no living organisms ever existed.

R: Physical environmental conditions do not support these areas.

A: In secondary productivity, no new organic matter is formed.

R: It is only utilising part of food manufactured by primary producers to building of consumer biomass.

A: Detritivores and decomposers hold up a part of nutrients contained in detritus.

R: Immobilised nutrients cannot be available for solubilisation after the death of saprotrophs.

A: Neither the community modifies environment, nor the environment forces the community to leave the place in the climax stage of succession.

R: Climax community is xerophytic in most of the types of succession.

A: Ecological pyramids of biomass are generally inverted in the sea.

R: Biomass of fishes far exceeds that of phytoplanktons.

A: Pyramid of biomass pyramid is always upright for the tree ecosystem.

R: Total biomass of a tree in a specific area is more than that of herbivores.

A: Niche becomes general and broader during biotic succession.

R: Species diversity increases, but organic matter is decreased.

A: Stratification helps in the accommodation of a large number and types of plants in the same area.

R: It is the occurrence of horizontal zonation in the ecosystem.

A: During succession, nutrient availability decreases while biomass level increases.

R: NCP (Net community productivity) remains the same during succession.

A: Decomposers are excluded from the food chains.

R: They act on all trophic levels of a food chain.

Decomposers act at each trophic level.

A: In hydrosere, reed swamp stage is followed by a floating plant stage.

R: Sedge meadow stage has amphibious herbaceous plants.