question_answer

In an ecosystem, the movement of nutrients is called cycling while the term 'flow' is used for energy. Give reason.

Answer:

Nutrients are required by organisms to sustain their life.

These nutrients are provided by earth and after the death and decay of organisms, they return back to the earth.

Thus, there is a constant exchange of nutrients between living and non-living components of ecosystem. On the other hand, the flow of energy in an ecosystem is always unidirectional, i.e. it never returns and there is decrease in energy content with the rise in trophic levels. Hence, the terms cycling and flow are the best suited for nutrients and energy, respectively.