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प्रश्न
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.
During the starch test, why was the leaf
(1) boiled in water
(2) boiled in methylated spirit
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उत्तर
(1) The leaf was boiled in water to destroy enzymes so that further chemical changes do not take place in the leaf.
(2) The leaf was boiled in methylated spirit to dissolve chlorophyll.
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संबंधित प्रश्न
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)
How would you demonstrate that green plants release oxygen when exposed to light?
ATP is needed for the dark reaction.
Name the following:
The green colouring matter of the plants.
Name the following:
Light in which the maximum rate of photosynthesis takes place.
Write the overall chemical equation for photosynthesis.
Name two plants having variegated leaves.
Given below is the diagram of an experimental set-up (final stage). Study the same and answer the following questions:
- What is the main aim of the experiment?
- Oxygen gas shown in the experiment is released from which of the raw materials?
- How would you confirm the presence of oxygen gas?
- Name the chemical substance which can be added in water to enhance the process/rate of release of oxygen gas.
- Draw a neat and labelled diagram of the same experiment for its initial stage.
