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Photosynthesis

Observe the p...

Question

Observe the picture below. The variegated leaves are used to determine the role of chlorophyll in photosynthesis. After adding Iodine solution, only green part of leaf show positive result. The possible reason for this is:

A

Iodine cannot diffuse into non-green parts of leaf.

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B

Iodine has more affinity towards towards green patches.

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C

Starch production takes place in green parts only.

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D

Starch production takes place in non-green plants.

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Solution

The correct option is C
Starch production takes place in green parts only.

Iodine solution is used to test the presence of starch in samples. With starch, iodine turns blue-black in colour. In the case of a variegated leaf, only green parts can trap sunlight and produce starch during photosynthesis whereas the non-green parts cannot. When iodine is added, it shows a positive result only in green parts as there is starch production in those areas.

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