noun, plural: stratified epithelia
The epithelial tissue (also called epithelium) is one of the different types of animal tissues. It is made up of one or more layers of cells closely packed together. It is primarily involved in protecting the underlying structures, secretion, regulation, and absorption. The epithelium may be classified based on the number of layers that make it up. In particular, the epithelium may be simple or stratified. In comparison, the simple epithelium is composed of a single layer of epithelial cells whereas the stratified epithelium is made up of a multiple layer of epithelial cells.
A stratified epithelium is a type of epithelial tissue that is composed of more than one layer of epithelial cells. The basal layer is the only one that is in contact with the basal lamina. This layer is also the one that undergoes mitotic division producinh cells in the upper layers.
The stratified epithelium is found in the skin wherein the apical layer becomes heavily keratinized before dying, and is also continuously shed as squames. Stratified epithelia usually have a mechanical or protective role.
The stratified epithelium may be categorized based on the type of cells that makes it up. In particular, it may be squamous (flat-like), cuboidal (cube-like), or columnar (column-like).
- stratified epithelial tissue