Question

how do guard cells regulate opening and closing of stomata

Answer 1

Guard cells are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata.

Answer 2

The opening and closing of stomata is regulated by the amount of water and solutes present in the guard cells.As the stomata opens during the daytime,the diffusion of gases in and out starts fulfilling the need for photosynthesis and respiration.If for any reason,the water content of the leaf is falling short ,the guard cells fail to remain turgid,rather,they turn flaccid,thereby closing the stomatal aperture.

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