The stratum basale is the deepest layer of the |epidermis|, consisting of a single row of columnar or cuboidal cells. The epidermal cells originate from this layer and new cells are continually being produced. Some of these cells make the |protein| ~keratin~, which toughens them. Others produce melanin, the substance that gives skin color. As the cells in this layer increase in number, they are pushed outward and become part of the |stratum granulosum|.
