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[A]: Light is very important external fa...

[A]: Light is very important external factor of transpiration.
[R]: Light induces stomata! opening and darkness stomata! closure. Thus the rate of transpiration increases in light and de- creases in dark.

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reson are false.

Text Solution

Verified by Experts

The correct Answer is:
A
Light has got no direct effect on the rate of transpiration but indirectly int affects the ratin in two ways firstly by controlling the stomatal opening and sccondly by affecting the tempetature. With the incrase in the light intensity the rate of transpiration increases because the stomata get opened and the temperature incrases. The rate of transpiration markedly in light and decrases in dark. There is a close relationship between the opening of stomata and presure of light.
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