Biology
Give suitable explanation for the following:
Some plants show wilting of their leaves at noon even when the soil is well-watered.
Transpiration
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Answer
In some plants, e.g. balsam, the leaves of the plants wilt during the midday inspite of the fact that there is plenty of water in the soil because during the midday the rate of transpiration exceeds the rate of absorption of water by the roots. The cells, therefore, lose turgidity. In evening or at night, the stomata are narrowed or constricted and the temperature is not high, therefore, there is no loss of water through transpiration and turgidity of leaves is re-acquired and they stand erect.
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