PHOTOSYNTHESIS

PHOTOSYNTHESIS

    • Photosynthesis is a vital physiological process where in the chloroplast of green plants synthesizes sugars by using water and carbon dioxide in the presence of light.
    • Photosynthesis literally means synthesis with the help of light i.e. plant synthesize organic matter (carbohydrates) in the presence of light.
    • Photosynthesis is sometimes called as carbon assimilation (assimilation: absorption into the system). This is represented by the following traditional equation.
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    • During the process, the light energy is converted into chemical energy and is stored in the organic matter, which is usually the carbohydrate. One molecule of glucose for instance, contains about 686 K Calories energy. CO2 and water constitute the raw material for this process and oxygen and water are formed as the by products during photosynthesis.
    • Stephen Hales (1727) first explained the relationship between sunlight and leaves and Sachs (1887) established that starch was the visible product of photosynthesis.
    • Of the total world’s photosynthesis 10 per cent is carried marine water algae and aquatic plants (ocean).
    • Basically, photosynthesis is process of conversion of light energy into chemical energy.
    • Light not only behaves as a wave but also has energy particles called photons.
    • The energy of photons is different for light of different wavelengths.
    • Atmosphere contains about 2.2 x 103 tonnes of CO2, while, oceans have high CO2 concentration 11 x 103 tonnes. Only about 1011 or 100 billion tones of carbon is converted into organic forms of about 225 billion tones of organic matter.
    • According to old concept aquatic photosynthesis is 90% and 10% is terrestrial photosynthesis. But according to new concept 40% of total photosynthesis is aquatic photosynthesis.


Last modified: Wednesday, 6 June 2012, 5:26 PM