PLANT PHYSIOLOGY
TRANSPORT IN PLANT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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increase.
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decrease.
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stay the same.
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you would not be able to determine a difference in rate.
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Detailed explanation-1: -At low temperatures, plants dehydrate because of restricted water uptake. Under these conditions, rapid stomatal closure (i.e., hours after first being exposed to cold stress) limits water loss. This mechanism occurs in cold-tolerant, but not cold-sensitive species (Wilkinson et al., 2001).
Detailed explanation-2: -The loss of water as vapor from plants at their surfaces, primarily through stomata. rates increase; when they are closed, transpiration rates decrease. A region of still air near the surface of a leaf through which water must diffuse en route to the atmosphere.
Detailed explanation-3: -When there is no breeze, the air surrounding a leaf becomes increasingly humid thus reducing the rate of transpiration. When a breeze is present, the humid air is carried away and replaced by drier air.
Detailed explanation-4: -At higher temperatures, the stomata of the leaves close to prevent further water loss, reducing the transpiration rate. However, at very low temperatures, the plants enter a state of dormancy and transpiration comes to a standstill. Therefore, temperature is a major external factor affecting plant transpiration.