Function of Guard Cells:
Guard cells are specialized cells found in the epidermis of leaves that surround and control the opening and closing of stomata. Stomata are small pores on the surface of leaves that allow for gas exchange, including the intake of carbon dioxide and the release of oxygen during photosynthesis. The main function of guard cells is to regulate the opening and closing of stomata to control the exchange of gases and water vapor between the plant and its environment.

Effect of Water Entry on Guard Cells:
When water enters through stomatal force, it causes the guard cells to swell and become turgid. This increase in turgidity leads to the opening of the stomatal pore. The movement of water into the guard cells causes them to change shape, becoming kidney-shaped with a thicker inner wall and a thinner outer wall. This change in shape creates a pore between the two guard cells, allowing for gas exchange to occur.
As water continues to enter the guard cells, they become more turgid, leading to a further opening of the stomatal pore. This allows for an increase in the uptake of carbon dioxide for photosynthesis and the release of oxygen and water vapor. The opening of stomata also enables the plant to regulate its water balance by controlling the transpiration rate.
Overall, the entry of water through stomatal force plays a crucial role in the regulation of stomatal opening and closing by affecting the turgidity of guard cells. This mechanism helps plants to adapt to changing environmental conditions and optimize their gas exchange processes for efficient photosynthesis.