SIMPLE EPITHELIA

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 These epithelia, also called unilaminar epithelia, consist of only a single layer of cells. Each cell of this epithelial layer has a basal surface which rests on the basement membrane, and a free surface which faces the cavity (or lumen) of an organ' or a body part.
Simple Epithelia

A simple epithelium consists of only a single layer of cells. Each cell has a free surface and a basal surface which rests on the basement membrane. The lateral margins of the adjacent cells are closely apposed and are held together by cell junctions; therefore, in a surface view, the cells appear to form a mosaic. According to the shape of their component cells, the simple epithelia are further classified into the following three types:

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SIMPLE SQUAMOUS EPITHELIUM

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