can someone explain me the carbon cycle please ?

Carbon Cycle-

Main key process involved in carbon cycle are photosynthesis and respiration. 

1. In photosynthesis carbon-dioxide and water produce carbohydrate and oxygen. While respiration oxidize food to give carbon-dioxide and water.

2. In ocean and in rocks carbon-dioxide dissolves readily in water. In rock it get stored as calcium carbonate.

3. Carbon can either be liberated to atmosphere through respiration or can be passed to animal when being eaten or remain in plant even after death.

4. After death of plant or animal decomposition take place and carbon dioxide get released to atmosphere. They can also be buried inside the earth and converted to coal or natural gas . Natural gas and Coal are fuels and on combustion they release carbon dioxide back into the atmosphere.

5. Carbon dioxide goes into the oceans and excess of carbon-dioxide can cause global warming

Carbon cycle is the biogeochemical cycle which includes the movement of carbon between biosphere, oceans, atmosphere and geosphere. All living things are made up of carbon. Carbon is found in various forms such as carbon dioxide, carbonate etc. During the day, plants absorb CO₂ from the atmosphere due to the process of photosynthesis and release back CO₂,during night when they respire. Further when the plants die, their remains gets converted into the fossils like coal which contain carbon. When animal eats these plants, the carbon present in the plant gets transferred to the body of the animal. The remains of the animals after their death, gets converted into fossil fuels, inorganic carbonates (shells) etc. Also, respiration and decomposition of dead remains of these animals, releases back the carbon to the atmosphere which is again used by plants during the process of photosynthesis and the cycle goes on. Combustion of fuels also releases carbon dioxide to the atmosphere.

Source: NCERT biology class IX

The importance of carbon cycle is that it helps in movement of carbon through all the spheres of earth and maintaining optimum concentrations in each sphere. It also helps in the regulation of the climatic conditions. A minor disturbance in the balance between the carbon concentrations in these spheres may result in serious consequences like global warming.

Carbon enters life forms through the process of photosynthesis. Photosynthesis is the process by which plants prepare food in the presence of sunlight and chlorophyll. During photosynthesis, carbon dioxide and water combine to produce glucose and oxygen. This changes the atmospheric carbon into glucose molecules.

Hope this answers your question.

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