Written description of how carbon moves through the biosphere, atmosphere, hydrosphere, and geosphere.

Carbon is present in the biosphere and other systems of the planet and is an essential part of life. Carbon moves through these systems by feeding the heterotrophs of other organisms, through the consumption of dead organisms. When oxygen is present, there is aerobic respiration, which releases carbon dioxide into the surrounding air or water. It plays an important role in the structure, biochemistry, and nutrition of all living cells.