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DictionarySeeepitheliumgerminal epithelium
germinal epithelium[′jər·mən·əl ‚ep·ə′thē·lē·əm] (embryology) The region of the dorsal coelomic epithelium lying between the dorsal mesentery and the mesonephros. germinal epithelium
epithelium [ep″ĭ-the´le-um] (pl. epithe´lia) (Gr.) the cellular covering of internal and external surfaces of the body, including the lining of vessels and other small cavities. It consists of cells joined by small amounts of cementing substances. Epithelium is classified into types on the basis of the number of layers deep and the shape of the superficial cells.ciliated epithelium epithelium bearing vibratile, hairlike processes (cilia) on its free surface.columnar epithelium epithelium whose cells are of much greater height than width.cuboidal epithelium epithelium whose cells are of approximately the same height and width, and appear square in transverse section.germinal epithelium thickened peritoneal epithelium covering the gonad from earliest development; formerly thought to give rise to germ cells.glandular epithelium that composed of secreting cells.pigmentary epithelium (pigmented epithelium) that made of cells containing granules of pigment.sense epithelium (sensory epithelium) neuroepithelium (def. 1).simple epithelium that composed of a single layer of cells.squamous epithelium that composed of flattened platelike cells.stratified epithelium epithelium made up of cells arranged in layers.transitional epithelium a type characteristically found lining hollow organs, such as the urinary bladder, that are subject to great mechanical change due to contraction and distention; originally thought to represent a transition between stratified squamous and columnar epithelium.ger·mi·nal ep·i·the·li·uma cuboidal layer of peritoneal epithelium covering the gonads, previously thought to be the source of germ cells, hence the name.ger·mi·nal ep·i·the·li·um (jĕr'mi-năl ep'i-thē'lē-ŭm) A cuboidal layer of peritoneal epithelium covering the gonads, formerly thought to be the source of germ cells. germinal epithelium a cell layer found on the outer surface of the vertebrate OVARY and lining the seminiferous tubules of the TESTIS, which gives rise to follicle cells in females and to spermatogonia in males. In males it also produces SERTOLI CELLS which nourish the developing sperms. |