Stratified columnar epithelium
noun, plural: stratified columnar epithelia
A type of stratified epithelium in which the topmost layer is made up of columnar epithelial cells, such as those found in the conjunctiva of the eye, the lobar ducts, and in certain parts of the male urethra, vas deferens, the uterus, anus, and the pharynx
A stratified epithelium is an epithelial tissue composed of more than one layer of epithelial cells. It differs from a simple epithelium in a way that the latter consists only one layer of epithelial cells. The basal layer of the stratified epithelium is the only one that is in contact with the basal lamina. The cells in the basal layer divide mitotically resulting in more cells atop the basal layer. The apical cells are regularly replaced by new cells produced through mitosis. The stratified epithelium may be further classified based on the type of cells located at the surface: squamous, columnar, or cuboidal.
In a stratified columnar epithelium, the topmost layer consists of columnar epithelial cells. Middle and basal layers consist of cuboidal and columnar epithelial cells, respectively. The stratified cuboidal epithelium is exemplified by those found in the conjunctiva of the eye, the lobar ducts, and in certain parts of the male urethra, vas deferens, the uterus, anus, and the pharynx. The stratified columnar epithelium is associated with secretion and protection.
- stratified columnar epithelial tissue