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Question
Describe an experiment to prove that sunlight is necessary for photosynthesis.
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Solution
Experiment to prove that sunlight is necessary for photosynthesis:
a. A potted plant is kept in the dark for two days to destarch the leaves.
b. A part of a leaf is covered with a black paper by clip.
c. Now the plant is kept in the light for few hours.
d. The leaf is plucked and is boiled in water and is then decolourized with
alcohol.
e. The portion of leaf which received light turns blue with iodine because
photosynthesis took place in that part of leaf.
f. The part of leaf which was covered with black paper remains colourless
because photosynthesis could not take place in the absence of sunlight.
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