Give scientific reasons for the following statements :
Energy flow is always unidirectional in an ecosystem.

Explanation

The solar energy enters in an ecosystem through the process of photosynthesis performed by green plants. The energy that is captured by grccn plants does not rcvcrt back to the sun.
From green plants energy passes to upper trophic levels of consumers. Energy obtained by herbivores does not come back to the green plants. As it moves progressively through the various trophic levels it is no longer available to the previous level.
Thus, energy flow is always unidirectional in an ecosystem.