Leaf epidermal cell. Transmission electron micrograph (TEM) of a section through an upper epidermal cell (at left) of a leaf. The thick layer on the right is the cuticle, a coating of waxy material secreted by the epidermis. It provides some physical protection and reduces the amount of water lost from the leaf by evaporation. The part of the epidermal cell's wall (pale grey) that lies next to the cuticle is considerably thickened. The pale bodies within the epidermal cell are starch grains, the product of photosynthesis, contained in chloroplasts. Magnification: x22,500 at 7.5x8 inch size.