Epithelial Tissues exist in many structural forms. In general it either covers or lines some thing and typically consist of renewable sheets of cells that have surface specialization adapted for their specific role. Usually basement membranes prates epithelial tissues from underline adjacent tissues. Epithelial tissues absorb e.g.,( the lining of the small intestine) transport e.g.,(kidney tubules)excrete e.g., (sweat gland) protect e.g., ( the skin) and contain nerve cells for sensory reception e.g., ( the taste buds in the tongue) .
The size shape and arrangement of epithelia cells are directly related to this specific function.Epithelial tissues are classified on the basis of shape and the number of layers present. Epithelium can be simple consisting of only one layer of cells or stratified consisting of two or more stacked layers. Individual; epithelial cells cab flat (squamus epithelial), cube shape (cuboidal epithelium), or column like (columnar epithelium). Cells of pseudo stratified ciliated columnar epithelium possess cilia and appear stratified or layered but they are not hence the prefix pseudo. They look layered because their nuclei are at two or more levels with in the cells of the tissues.
The size shape and arrangement of epithelia cells are directly related to this specific function.Epithelial tissues are classified on the basis of shape and the number of layers present. Epithelium can be simple consisting of only one layer of cells or stratified consisting of two or more stacked layers. Individual; epithelial cells cab flat (squamus epithelial), cube shape (cuboidal epithelium), or column like (columnar epithelium). Cells of pseudo stratified ciliated columnar epithelium possess cilia and appear stratified or layered but they are not hence the prefix pseudo. They look layered because their nuclei are at two or more levels with in the cells of the tissues.