what are guard cell ?Explain their role in regulating transpiration.

Dear Student, Raja

Guard cells are the specialised cell that are usually found on the undersite of a plant leaf. They occur in pairs and are kidney shaped so that a pore, or stomata, exists between them.

Guard cells plays an important role in the regulation of  transpiration. During the warm conditions when the plant is undergoing water-stress, the guard cells become flaccid so that the stomata closes thus peventing the further loss of water and vice-versa.

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