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प्रश्न
Describe fully one experiment with potted green plant to show that starch is not produced in the leaves when carbon dioxide is not available (diagrams essential)
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उत्तर
Experiment to show that starch is not produced in the leaves when carbon dioxide is not available:
a. A potted plant is kept in the dark for two days to destarch the leaves.
b. Take a wide mouth bottle and fill 1/ 3'd of it with caustic potash solution.
c. Insert half part of the leaf of potted plant in the bottle and do not let the leaf to
touch the solution in the bottle.
d. The apparatus is kept in sunlight for few hours.
e. The leaf is plucked and tested for starch.
f. Only the portion of the leaf which is outside the bottle turns blue and the part of
the leaf inside the bottle remains colourless because it did not get C0 2 for
photosynthesis. All the C02 present in the bottle was absorbed by caustic
solution.
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संबंधित प्रश्न
A healthy oat seeding in a pot is transferred from light to any airy but completely dark room. How would it differ from its original condition in appearance after about a week? Explain the difference.
Two healthy green plants were placed in the dark for 24 hours. They were then set up, as shown in the figure, for 4 hours. Then a leaf was taken from each plant and
the chlorophyll was removed from the leaves:
( i) What is the next and final step in this experiment?
( ii ) What would be the results of the final step?
( iii ) Why was it necessary to grease the glass sheet?
( iv ) What hypothesis is being tested in this experiment?
Mention one difference between the following on the basis of what is given in bracket.
Chlorophyll and chloroplast (part of plant cell)
The chemical substance used to test the presence of starch in the cell of a leaf is ______.
Photosynthesis in green plants is directly and indirectly dependent on so many plant structures.
Explain briefly the role of the following structures in this process Guard cells.
Photosynthesis in green plants is directly and indirectly dependent on so many plant structures.
Explain briefly the role of the following structures in this process is Cuticle.
Given alongside is the diagram of an experimental set-up:
Will it work satisfactorily? Given reason.
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.
Draw a neat diagram of a chloroplast and label its parts.
Match the terms given in column A with column B:
| Column A | Column B | ||
| (a) | Chlorophyll | (i) | Removes/absorbs CO2 |
| (b) | Methylated spirit | (ii) | Tests presence of starch |
| (c) | Potassium hydroxide | (iii) | Traps solar energy |
| (d) | Iodine solution | (iv) | Produces oxygen |
| (e) | Water | (v) | Bleaches chlorophyll |
