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प्रश्न
How would you test the presence of starch in leaves?
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उत्तर
Experiment to test the presence of starch in leaves:
- Take two healthy green potted plants of the same type.
- Keep one potted plant in a dark room for one or two days in order to remove all the starch from the leaves.
- Keep the other plant in sunlight.
- Now, take one leaf from each potted plant and put a few drops of iodine solution on them.
- Note down the change in the colour of both the leaves.
- Observation: No blue-black colour will be observed on the leaves of the plant kept in the dark room. This indicates the absence of starch. Blue-black colour will be observed on the leaves of the plant kept in sunlight. This indicates the presence of starch.
- Concept insight: Plants prepare glucose during photosynthesis which gets stored in plants in the form of starch. Iodine turns blue-black when reacted with starch.
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