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Question
Green plants use carbon dioxide for photosynthesis and return oxygen to the atmosphere, even then carbon dioxide is considered to be responsible for greenhouse effect. Explain why?
Solution
CO2 gas is confined to the troposphere only and it forms nearly 0.03 per cent by volume of the atmosphere. With the increased use of fossil fuels, a large amount of carbon dioxide gets released into the atmosphere. Excess of carbon dioxide in the air is removed by the green plants and this maintains an appropriate level of it in the atmosphere. Green plants require carbon dioxide for the process of photosynthesis and which in turn emits oxygen, thus maintaining the balance in nature. Deforestation and the burning of fossil fuels increase the level of carbon dioxide, and this disturbs the balance in the atmosphere. The increased amount of carbon dioxide in the air is mainly responsible for global warming.
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