2023 · Q47
Energy and nutrients flow from one trophic level to another in an ecosystem. Which one of the following statements correctly describes the direction of flow of energy and nutrients in an ecosystem?
General KnowledgeBiology
- AEnergy flow is cyclic and nutrient flow is unidirectional.
- BEnergy flow is unidirectional and nutrient flow is cyclic.
- CBoth energy and nutrient flow are unidirectional.
- DBoth energy and nutrient flow are cyclic.
Explanation
Energy flows unidirectionally through trophic levels and is progressively lost as heat (roughly 90% at each transfer), so it cannot cycle back. Nutrients such as carbon, nitrogen and phosphorus are recycled between organisms and the environment, so their flow is cyclic.