How do guard cells control the opening and closing of stomata

The way for guard cells to control the opening and closing of stomata is to use chloroplasts to generate energy under light conditions, adjust the osmotic pressure of guard cells, and control the expansion and contraction of guard cells, thus controlling the opening and closing of stomata. The opening and closing of stomata is controlled by guard cells on leaves. Normal epidermal cells have no chloroplasts, but there are chloroplasts in guard cells, which can be used for weak photosynthesis by sunlight. Together with other factors of guard cells, they regulate the expansion and contraction of guard cells and control the opening and closing of stomata.