Any unit or bio system that includes all the organisms which function together in a given area where they interact with the physical environment is known as ecosystem.Autotrophs is an organism that can produce its own food using light, water, carbon dioxide, or other chemicals.A heterotrophs is an organism that eats other plants or animals fir energy and nutrients.Primary consumers are herbivores feeding directly on living plants(producers)or plant remains.For example:Copepods, zooplankton, benthos etc.and Secondary consumers are carnivores that feed on primary consumers(herbivores).For example:chiefly insects, fishes, molluscs etc.
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