produced when plants grow. recycled when organisms die. lost when animals and plants die. formed when new animals are born.
I gave my students this multiple choice question: In any ecosystem, organisms interact with biotic and abiotic parts of the environment. As a result of all of the interactions, the matter within the system is

Only one answer is correct among these 4 choices:
- produced when plants grow.
- recycled when organisms die.
- lost when animals and plants die.
- formed when new animals are born.

Could you tell me which one is correct?

recycled when organisms die.