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In the experiment to demonstrate that st...

In the experiment to demonstrate that starch is made as food by the process of photosynthesis, the plucked leaf is first boiled in water for about 3 to 5 minutes in order to :

A

remove chlorophyll from leaf cells

B

break down the cell membranes of leaf cells

C

soften the brittle leaf

D

convert starch into glucose so that it can be tested easily

Text Solution

Verified by Experts

The correct Answer is:
B
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Knowledge Check

  • In the experiment to show that light is necessary for photosynthesis, the pluked leaf is boiled in ethanol and then washed with water. After this, it is tested for the presence of a carbohydrate by a chemical which is:

    A
    salt solution
    B
    sugar solution
    C
    iodine solution
    D
    starch solution

  • In an experiment to test the presence of starch in a leaf, the plucked leaf is first boiled in water for a few minutes. This is an important step in the experiment because it:

    A
    converts glucose made in the leaf into starch
    B
    dissolves chlorophyll present in the green leaf
    C
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    D
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  • In the activity to demonstrate that chlorophyll is essential for photosynthesis, a plotted plant with variegated leaves is first taken and kept in a dark room for three days after which it is kept in sunlight for about six hours. The leaf is then plucked, the green areas traced and then the leaf is first dipped in boiling water for a few minutes and then immersed in a beaker containing alcohol as shown in diagram below: The reason why leaf is immersed in hot alcohol is to:

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    stop photosynthesis
    C
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    D
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