The Epidermis

The epidermis is the uppermost layer of the skin consisting of a continually changing layer of stratified epithelium (skin tissue composed of several layers of skin cells).

The appearance of the skin greatly depends upon the health of this top layer of skin tissue, in conjunction with properly functioning systems of the underlying dermis.

The epidermis has an amazing self-renewing system that facilitates sloughing off and complete replacement of the outer skin cells over a 28 day cycle.

Although it has a waterproof outer layer, the epidermis does allow water to carry some nutrients to its outer-most living cells.

The epidermis consists of five individual layers: Stratum Germinativum; Stratum Spinosum; Stratum Granulosum; Stratum Lucidum and Stratum corneum.

The Stratum Germinativum is the deepest epidermal layer comprising living cells that are in close contact with the dermis and from where the basal cells receive nourishment. It also contains pigment (melanin) producing cells and is the site for cell division - new cell creation which pushes newer cells up to the surface.

The next three layers in order are the Stratum Spinosum, Stratum Granulosum, and Stratum Lucidum. The Stratum Lucidum is believed to be the skin's water barrier zone.

The uppermost layer of the epidermis is known as the Stratum Corneum, consisting mainly of dead flakes of keratin protein that continually slough off. This sloughing off is known as desquamation.

Next Article: The Dermis ->