AP BIOLOGY

Detailed explanation-1: -The guard cells are bean-shaped with an inner inwardly curved wall towards the stomatal pore. The wall of Guard cells towards the stomatal pore is thick to facilitate the opening of the stomatal pore during transpiration.

Detailed explanation-2: -The guard cells are generally crescent-shaped with blunt ends (kidney-shaped) in surface view (Fig. 22.3D) and often have ledges of wall material on the upper and lower sides.

Detailed explanation-3: -Stomata are the bean-shaped guard cell that is responsible for the gas exchange in plants.

Detailed explanation-4: -In plants, gases are exchanged through small openings called stomata which are present mostly on the lower surface of leaves and on green stems. Each stoma has two bean-shaped cells called guard cells.

Detailed explanation-5: -The opposing inner walls of the guard cells are thick and inelastic. The remaining walls are thin and elastic. But Guard cells have mostly elastic walls. This is because the stomatal pores have to continuously open and close to allow exchange of gases through them.