|palisade layer |
A layer of cells just below the upper surface of most leaves, consisting of cylindrical cells that contain many chloroplasts and stand at right angles to the leaf surface. It is the principal region of the leaf in which photosynthesis is carried out and lies above or to the outside of the spongy parenchyma. Also called palisade parenchyma. See more at photosynthesis.
The light of the sun easily penetrates to the cells of the palisade layer, giving the energy needed to make the starch.
Under the upper epidermis is a layer of green cells closely packed together (called collectively the palisade layer).