To draw: A food web and describe the consequences of humans “abstain from eating blue crab” on the food chain.
Concept introduction: Food chain is the transfer of food energy from one trophic level to successive trophic levels. In other words, food chain refers to the way an organism obtains food in the ecosystem. The primary producers (plants) are eaten by the herbivores which in turn are eaten by carnivores. The carnivores are further eaten up by the top carnivores. When the organisms die, they are decomposed by the action of decomposers and return back the nutrients to the soil. In this way, food chain continues. The food chain never exists in isolation. The food chains are interconnected to form “food web”.
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CAMPBELL BIOLOGY-W/MOD.MASTERBIOLOGY
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