Give a brief overview of the carbon cycle. Include the source of carbon that enters ecosystems, how ...

Plants take up CO2 from the atmosphere and then incorporate the carbon into their tissue. Animals then eat plants and gain carbon. Carbon is used for all the tissues and molecules of living organisms, such as carbohydrates, fats, and proteins, and as an essential ingredient in DNA. When animals and plants die, their tissues are metabolized by decomposers and much partially degraded biomass (especially from plants) is then deposited into soils. At each stage along the way, some carbon is released back to the atmosphere as carbon dioxide. The use of fossil fuels (previously undecomposed organic materials) causes stored CO2 to be released to the atmosphere. This is occurring at very high rates and is contributing to global warming.