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Question
A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.
Why was the plant placed in the dark before beginning the experiment?
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Solution
Before beginning the experiment, the plant was kept in dark in order to destarch it, i.e. to remove the pre-existing starch from the storage organs.
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A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.
What aspect of photosynthesis was being tested?
Choose the Correct Answer:
The main difference between chlorophyll ‘a’ and ‘b’ is:
Give reasons/explain:
During the starch test, the leaf is boiled in methylated spirit.
