B.13C_Carbon_onlevel – 04

Under certain temperature and pressure conditions, sediments on the ocean floor can become fossil fuels, such as oil, natural gas, and coal. After being stored for millions of years, the fuels are extracted. When the fuels are burned for energy, carbon dioxide is given off and enters the atmosphere. This carbon dioxide is available to enter the carbon cycle again. The path of carbon through limestone and fossil fuels is known as the geological carbon cycle.
Carbon also cycles in a much quicker path known as the biological carbon cycle. Carbon dioxide in the air is taken in by plants. The plants use carbon dioxide for photosynthesis. Through this process, the carbon in carbon dioxide is used to make the glucose molecule. Animals obtain this carbon by eating plants and other animals. The glucose is broken down during respiration in plant and animal cells. Carbon dioxide is a product of respiration. Carbon dioxide is released into the air by plants and animals. The carbon dioxide can be used in the cycle again.
Carbon is stored in dead plants and animals. It is also stored in animal wastes. The stored carbon can re-enter the carbon cycle when decomposers act on the dead matter and wastes. The carbon dioxide that is a product of the decomposition process enters the atmosphere and is available to cycle again.
When the carbon cycle is disrupted, the consequences can negatively impact the environment. Carbon dioxide levels in the atmosphere are increasing in several ways. Carbon dioxide is entering the atmosphere through the combustion of fossil fuels by automobiles and factories.
