Q. 83.8( 6 Votes )
Why leaves become yellow in the absence of light?
Presence of light is quite necessary for plants because in presence of light plants by the process of photosynthesis synthesizes their food. In the absence of light the process of photosynthesis is not possible.
For synthesis of food presence of a pigment called chlorophyll is also necessary which absorbs the sunlight and helps in photosynthesis process. The colour of this pigment is green and therefore most of the plants exhibit green colour.
But when there will be no sunlight, no photosynthesis takes place and as plant will not get energy there will be no chlorophyll in the plant after some time and thus plant start becoming yellow in the absence of light.
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Study the given diagram:
Name the parts ‘A’ and ‘B’ and state one function of each.
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