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Question
Explain why, a food chain usually cannot have more than three or four steps.
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Solution
At each trophic level in a food chain, a large portion of the energy available is utilised for the maintenance of organisms in that trophic level and is lost as heat. Food chains usually cannot have more than three or four steps because the energy available for organisms in any additional step will be so small that it will be insufficient to sustain the life of those organisms.
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