The stratum basale (basal layer, sometimes referred to as stratum germinativum) is the deepest layer of the five layers of the epidermis, which is the outer covering of skin in mammals.
The stratum basale is a continuous layer of cells. It is often described as one cell thick, though it may in fact be two to three cells thick in glabrous (hairless) skin and hyperproliferative epidermis (from a skin disease).
The stratum basale is primarily made up of basal keratinocyte cells, which can be considered the stem cells of the epidermis. They divide to form the keratinocytes of the stratum spinosum, which migrate superficially. Other types of cells found within the stratum basale are melanocytes (pigment-producing cells), Langerhans cells (immune cells), and Merkel cells (touch receptors).
Read more about Stratum Basale: Additional Images
Famous quotes containing the word stratum:
“If you chance to live and move and have your being in that thin stratum in which the events that make the news transpire,—thinner than the paper on which it is printed,—then these things will fill the world for you; but if you soar above or dive below that plane, you cannot remember nor be reminded of them.”
—Henry David Thoreau (1817–1862)