Explain the mechanism of opening and closing of stomata

Mechanism of opening and closing of stomata






Some plants open/unfold/unroll their stomata in the day time and shut/close them in the night time. It is the responsibility of stomata for transpiration and the movement of guard cells via actions. The inner concave side of the guard cell which opens the stomata is thicker than the outer convex side.



The two guard cells are attached at their ends and stomata is exists/present between them. When guard cells gain water and become turgid, then the stomata open. When guard cells lose water and become flaccid, then the stomata close.




The sunlight causes the movement of potassium ion through the epidermal cells to guard cells. Water also flows with these ions and enters in stomata of guard cells. The guard cells become turgid and stomata opensun/fold/unroll. Then the stomata begin to synthesize/make glucose i.e. become hypertonic. 



As the sun sets and sunlight starts decreasing,  the concentration of glucose also decreases. The potassium ions starts to flow back in epidermal cells and water molecules also starts to flow back to epidermal cells. The guard cells become flaccid/soft and this causes the closure of stomata. It also decreases/lower/lessen the rate of transpiration/evaporation.

No comments