Final answer:
A food chain is a sequence of organisms in which each organism serves as a source of food for the next organism. It represents the flow of energy and nutrients through different trophic levels in an ecosystem.
Step-by-step explanation:
A food chain is a sequence of organisms in which each organism serves as a source of food for the next organism. It represents the flow of energy and nutrients through different trophic levels in an ecosystem. For example, in a simple food chain, grass is eaten by a grasshopper, which is then eaten by a frog, which is finally consumed by a snake.
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