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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.
During the starch test, why was the leaf
(1) boiled in water
(2) boiled in methylated spirit
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Solution
(1) The leaf was boiled in water to destroy enzymes so that further chemical changes do not take place in the leaf.
(2) The leaf was boiled in methylated spirit to dissolve chlorophyll.
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