What Are Squamous Epithelial Cells?

Squamous epithelial cells are flat cells as compared to the rectangular (columnar) and square (cubical) cells, states About.com. They are found in many body parts, including the cervix, the middle skin layers, the mouth and the lips.

Squamous epithelial cells are affected by the squamous cell carcinoma, the commonest type of oral cavity cancer, according to About.com. This cancer also occurs in the cervix and on the skin. Abnormal Pap smear results have indicated abnormalities in the squamous epithelial cells in the cervix. This means that the cells have developed an abnormality but are not yet cancerous.

While many people think that epithelial cells are only on the skin, the truth is that they are also present in deeper layers of the body, says Davidson College. Since squamous epithelial cells are flat and thin, they have a large surface area. In fact, they are the thinnest of all types of epithelial cells. Additionally, they have a larger nucleus that is elliptically shaped.

Because of their thin and flat shape, they act as good mediators of diffusion and filtration, says Davidson College. In this regard, they allow easy movement of molecules across their membranes.

Depending on the concentration gradients, some molecules such as carbon dioxide and oxygen pass freely across the membrane of squamous epithelial cells.