The nitrogen cycle is one of the cycles of matter and details the movement of various forms of nitrogen through the components of the environment. There are different forms of nitrogen, such as organic nitrogen, ammonia, nitrites and nitrates. Animals play a key role in the nitrogen cycle. Animals are consumers of nitrogen or nitrogenous products. They obtain the required nitrogen from plants or other animals, which they eat. Animals store nitrogen in their body in the form of proteins and nucleic acids (such as DNA). When animals die, their bodies act as sources of nitrogenous products. Decomposers (such as soil microbes), break down the nitrogen in animals' bodies and release it to be used by other consumers. Similarly, plants also act as both consumers and producers (after their death) of nitrogen.
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