consumer organism

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consumer organism In the widest sense, a heterotrophic organism that feeds on living or dead organic material. Two main categories are recognized:
a. macroconsumers, mainly animals (herbivores, carnivores, and detritivores), which wholly or partly ingest other living organisms or organic particulate matter
; and
b. micro-consumers, mainly bacteria and fungi, which feed by breaking down complex organic compounds in dead protoplasm, absorbing some of the decomposition products, and at the same time releasing inorganic and relatively simple organic substances to the environment. Sometimes the term ‘consumer’ is confined to macroconsumers, microconsumers being known as ‘decomposers’. Consumers may then be termed ‘primary’ (herbivores), ‘secondary’ (herbivore-eating carnivores), and so on, according to their position in the foodchain. Macroconsumers are also sometimes termed phagotrophs or biophages, while microconsumers correspondingly are termed saprotrophs or saprophages. Compare PRODUCER.