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प्रश्न
Using the destarched plant describe step by step how would you proceed to prove that in the absence of light the leaf cannot manufacture starch?
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उत्तर
- In a dark room, a leaf on the destarched plant is covered on either side with strips of black paper which are kept in place by paper clips or cellophane tape.
- Now the potted plant is kept in the light.
- After a few hours, the leaf is detached from the plant and the black strips are removed.
- Then the leaf is boiled in water for 2-3 minutes and then boiled in alcohol to remove the green chlorophyll.
- The leaf is then washed in water and tested with iodine.
- The region of the leaf that was under the black strip turns yellowish-brown showing that no starch was made, while the rest of the leaf turns bluish-black showing the starch was made in the presence of light.
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संबंधित प्रश्न
The solvent used to dissolve the chlorophyll pigments while testing a leaf for starch is Soda lime.
Put a tick (✓ ) against the most appropriate alternative in the following statement.
Which one of the following is an end-product of photosynthesis?
Given below is the overall chemical equation of photosynthesis which is incomplete in certain respects.
\[\ce{CO2 + H2O ->[Chlorophyll] C6H12O6 + H2O + O2} \]
Rewrite the equation in its complete form .
What is meant by a destarched plant? How can it be destarched?
A healthy croton plant bearing variegated leaves was kept in a dark cupboard to destarch it after which it was placed in sunlight for a few hours. One of the leaves was then plucked and an outline of the leaf marking the green and the non-green regions was drawn. The leaf was then tested for starch. Using the above information, answer the following questions:
- State the aim of the above experiment.
- Name the chemical used for testing the presence of starch.
- Why is the leaf boiled in water and alcohol before testing for the presence of starch?
- What change is seen on the leaf after the starch test?
- Give the chemical equation to represent the process of starch formation in plants.
Name the following:
The chemical substance used to test the presence of starch in the cell of a leaf.
The gas given out during photosynthesis is _____.
Write the reaction for photosynthesis?
The reactions of photosynthesis make up a biochemical pathway.
What is the end product of light and dark reactions of photosynthesis?
Expand the abbreviation - NADP.
