Explain carbon cycle in nature .(4 marks)
Carbon cycle is a biogeochemical cycle (recycle mechanism) by which appropriate levels of carbon concentration is maintained in the environment.
The key processes involved in carbon cycle are photosynthesis and respiration.
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In photosynthesis carbon-dioxide and water produce carbohydrate and oxygen. While respiration oxidise food to give carbon-dioxide and water.
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In ocean and in rocks carbon-dioxide dissolves readily in water. In rock it get stored as calcium carbonate.
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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.
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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.
- Carbon dioxide goes into the oceans and excess of carbon-dioxide can cause global warming.
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