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प्रश्न
What causes the opening and closing of guard cells of stomata during transpiration?
उत्तर
The tiny pores present on the surfaces of leaves, called stomata, help in the exchange of gases. Each stoma consists of bean-shaped or dumbbell-shaped guard cells. The epidermal cells surrounding the guard cells are modified to form subsidiary cells. The opening and closing of the guard cells is caused by a change in their turgidity. The inner walls of the guard cells are thick and elastic, while the outer walls are thin. The numerous microfibrils present in the guard cells facilitate the opening and closing of the guard cells.
At the time of the opening of the stomata, the turgidity of the guard cells increases. As a result, the outer walls bulge and the inner walls become crescent-shaped. The stomatal opening is facilitated by the radial arrangement of the microfibrils.
At the time of the closing of the stomata, the guard cells lose their turgidity, the outer and inner walls retain their original shapes, and the microfibrils get arranged longitudinally.
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संबंधित प्रश्न
The loss of water in the form of water vapour through stomata on leaves is known as ___________.
State whether the following statement is true or false. Rewrite the false statement correctly.
Transpiration is the loss of water from the roots of the plant.
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Define the termTranspiration
Define the term Transpiration stream
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Name the phenomenon being demonstrated.
Give a reason.
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Litmus paper is used to demonstrate transpiration from the leaves of the green plant.
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Transpiration takes place through ______.
Write a note on Transpiration.
Which one is not related to transpiration?
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