HORTICULTURE

Detailed explanation-1: -Guard cells regulate the opening and closing of stomatal holes, which are controlled by the process called osmosis. The entry of water into the stomata makes guard cells swell which leads to the opening of the stomata. The stomata close when the guard cells lose water and constrict, becoming flaccid and straight.

Detailed explanation-2: -angiosperms. …the epidermis are paired, chloroplast-containing guard cells, and between each pair is formed a small opening, or pore, called a stoma (plural: stomata). When the two guard cells are turgid (swollen with water), the stoma is open, and, when the two guard cells are flaccid, it is closed.

Detailed explanation-3: -In angiosperms, passive inflation of epidermal cells at high water potential pushes back on guard cells, causing stomata to close rather than open.

Detailed explanation-4: -When the water enters the cells, they swell and become bowed. This causes the guard cells to bend away from each other, thereby opening the stomata. Conversely, when guard cells lose potassium ions, water diffuses out of the cells by osmosis.

Detailed explanation-5: -Opening and closing of stomata are controlled by the turgor changes in the guard cells. In the dark, the guard cells lose water, become flaccid and the stomata close. In the light, the guard cells absorb water by osmosis, become turgid and the stomata open.