Epithelium (epi- + thele + -ium) is ane o the fower basic teepes o ainimal tishie, alang wi connective tishie, muscle tishie an nervish tishie. Epithelial tishies line the cavities an surfaces o bluid veshels an organs ootthrou the bouk. An ensaumple is the epidermis, the ootermost layer o the skin.
Teeps o epithelium
Thare are three preencipal shapes o epithelial cell: squamous, columnar, an cuboidal. Thir can be arranged in a single layer o cells as semple epithelium, either squamous, columnar, cuboidal, pseudo-stratified columnar or in layers o twa or mair cells deep as stratifee'd (layered), aither squamous, columnar or cuboidal. Aw glands are made up o epithelial cells. Functions o epithelial cells include secretion, selective absorption, pertection, transcellular transport, an sensin.
Epithelial layers conteen na bluid veshels, sae thay maun receive nourishment via diffusion o substances frae the unnerleein connective tissue, throu the basement membrane. Cell junctions are weel-employed in epithelial tishies.