THE CARBON CYCLE

THE CARBON CYCLEAiyna Ali & Jade Lutchman THE CARBON CYCLE

Diagram of the Carbon Cycle

What is the Carbon Cycle?: The carbon cycle is the natural cycling of carbon atoms between rocks,vegetation,oceans and the atmosphere.The carbon cycle begins with the reservoir of carbon dioxide molecules present in the air and bicarbonate molecules present in water. Carbon atoms from CO2 become the carbon atoms of the organic molecules making up a plants body through the process of photosynthesis. The carbon atoms then become part of the tissues of all the other organisms by moving into the food webs. A Carbon atom may be respired and return to the atmosphere and in aquatic systems it will be returned to the inorganic carbonate in solution. Other processes are significant such as geological sedimentation and limestone formation of carbon in the oceans, which removes carbon from solution and weathering and combustion of fossil fuels.Atmospheric carbon: The troposphere has 0.035 percent of carbon dioxide gas. Carbon dioxide is removed from the atmosphere via photosynthesis and is added when plants ,animals and microorganisms respire or when carbon containing materials such as coal or wood is burned.Organic compounds in plants: Organic substances such as carbohydrates, fats and proteins are produced when plants use the carbon in carbon dioxide .The pigment chlorophyll is also an organic substance and has the formula, C55H72N4 O5Mg ,showing 55 carbons in each molecule.Organic compounds in consumers Primary consumers obtain their organic compounds through eating plants .The energy released may be passed on through the trophic levels. Carbon in freshwater and marine ecosystems Gaseous carbon dioxide dissolves in water to form hydrogen carbonate ions (HCO3-).Large quantities of carbon are also trapped in the form of carbonates in sea bed sediments, which over millions of years will form sedimentary deposits .In some coastal waters in the tropics, coral reefs lock up carbon as calcium carbonate .Areas where carbon are locked up, for example in the oceans or in the stems of trees, are known as carbon sinks.

All living organisms are connected via the carbon cycle.