Question 11
Will a leaf taken from a potted plant kept in a dark room for a few days turn blue-black when tested for starch? Give reason for your answer.

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Solution

No, a leaf from a potted plant kept in dark will not turn blue-black when tested for the presence of starch.
Plants perform photosynthesis only in the presence of sunlight. A leaf kept in dark for a few days cannot perform photosynthesis and all the stored starch would have been used up by the leaf; no fresh starch would be present in the leaf. Hence, the leaf will not turn blue-black when tested for starch.

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Photosynthesis

Standard VI Biology

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Question 11Will a leaf taken from a potted plant kept in a dark room for a few days turn blue-black when tested for starch? Give reason for your answer.

Question 11
Will a leaf taken from a potted plant kept in a dark room for a few days turn blue-black when tested for starch? Give reason for your answer.