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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.
संबंधित प्रश्न
(i) Fill in the blanks in the following equations of two chemical reactions:
(a) \[\ce{---+12H2O->[Light energy]C6H12O6 + --- + ----}\]
(b) \[\ce{--- 6O2->[Chlorophyll] 6 --- +6 ---- + Energy}\]
(ii) Name the two processes represented by the above two reactions.
(iii) State any two differences in these processes other than those already indicated in the reactions.
(iv) Which one of these two reactions is the supporter of all life on earth?
Identify the false statements and rewrite them correctly by changing the first or last word only.
Starch produced in a leaf remains stored in it for 2-3 weeks before it is used by other parts of the plant.
Enumerate the steps involved in testing a green leaf for the presence of starch.
A leaf is a food factory. Explain.
What is meant by a destarched plant? How can it be destarched?
Name the following:
The chemical substance used to test the presence of starch in the cell of a leaf.
Define Photosynthesis.
State whether true or false. If false, correct the statement.
Photosynthesis produces glucose and carbon dioxide.
How does the light-dependent reaction differ from the light-independent reaction? What are the end product and reactants in each? Where does each reaction occur within the chloroplast?
Name two raw materials for photosynthesis.
