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प्रश्न
Given alongside is the diagram of an experimental set-up:

Would you take any step before starting the experiment? Describe this step and explain its necessity.
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उत्तर
Before starting the experiment, it is necessary to destarch the leaves of the plant by keeping the plant in complete darkness for 48 hours. This is because if the plant is not destarched, then the experiment will give false results because starch stored previously may be detected in the leaf placed in the beaker even if no starch is produced during the experiment.
संबंधित प्रश्न
Mention one difference between the following on the basis of what is given in bracket.
Chlorophyll and chloroplast (part of plant cell)
Are the following statement true or false? Give a reason in support of your answer.
Destarching of the leaves of a potted plant can occur only at night.
Why is it not possible to demonstrate respiration in a green plant kept in sunlight?
Complete the following by filling the blanks 1 to 5 with appropriate words/terms/phrases:
To test the leaf for starch, the leaf is boiled in water to ______ (1). It is next boiled in methylated spirit to ______ (2). The leaf is placed in warm water to soften it. It is then placed in a dish and ______ (3) solution is added. The region which contains starch, turns ______ (4) and the region which does not contain starch, turns ______ (5)
Given below is the representation of a certain phenomenon in nature. With four organisms 1-4.

Name one natural element which all the organisms 2-4 and even 5 are getting from No. 1 for their survival.
Given alongside is the diagram of an experimental set-up:

What alteration (s) will you make in it for obtaining expected result?
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.
What aspect of photosynthesis was being tested?
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.
Why was the plant placed in the dark before beginning the experiment?
Name the following:
Light in which the maximum rate of photosynthesis takes place.
Given below is the figure of an experimental set-up, showing a physiological act of the plants. Study and answer the following questions:

- What is the objective of this experiment?
- Name and define the process shown here.
- Why do we destarch the leaves before performing the experiment?
- How do we destarch the leaves?
- What will be the observation when we pour iodine solution over the bleached experimental leaf?
- Write a well-balanced equation for the above process.
