- Carbon is found in various forms on the Earth.
- It occurs in the elemental form as diamond and graphite, in the combined state as carbon dioxide, carbonate and bicarbonate salts in various minerals, while all biotic factors are based on carbon-containing molecules like carbohydrates, proteins, fats, nucleic acids and vitamins. The endoskeletons and exoskeletons of various animals are also formed from carbonate salts.
- Carbon is incorporated into life-forms through the process of photosynthesis which is performed in the presence of Sunlight by all life-forms that contain chlorophyll.
- Photosynthesis converts CO2 from the atmosphere or dissolved in water into glucose molecules.
- These glucose molecules are either converted into other substances or used to provide energy for the synthesis of other biologically important molecules.
- The utilisation of glucose to provide energy to living things involves respiration in which oxygen may or may not be used to convert glucose back to carbon dioxide.
- This CO2 goes back into the atmosphere.
- This is the broad outline of carbon cycle.
Hope you could get an idea from here.
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