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Requirements for Photosynthesis

The non-green...

Question

The non-green part of a variegated leaf, after the starch test, exhibits colour due to the absence of

A

brown

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B

blue black

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C

sunlight

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D

chlorophyll

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Solution

The correct options are
A brown
D chlorophyll
Variegated leaf is a leaf that contains both green and non-green parts. The starch test is performed on variegated leaves to prove that chlorophyll is essential for the photosynthesis. After the starch test, we observe that the non-green part of the variegated leaf exhibits brown colour. This is because chlorophyll is absent in these areas. Thus, no starch production. We can also observe that the green part of the variegated leaf exhibits blue-black colour due to the presence of starch. This is because chlorophyll is present in these areas and there is starch production.

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