The carbon cycle is one of the most important among the biochemical cycles. The carbon forms the major constituent elements of all the compounds and the organisms itself. The incorporation of the carbon into the living organism is known as the photosynthesis. The carbon dioxide and water are the raw material for the photosynthesis. The major source of carbon dioxide is the atmosphere; from there it gets incorporated into the plants. The plants are eaten up by the animals there by reaching the entire food chain and become part of organism and get transferred to successive levels. Carbon is incorporated in the form of organic compounds.
By the process of decomposition, combustion and respiration of producers and decomposers the carbon dioxide returns back to the atmosphere. Some amount of the carbon may return to the deep sedimentation process. The part of the sedimentary deposits gets released to the atmosphere by the combustion of the fossil fuels there by returning to the carbon dioxide into the atmosphere.