Mathematics. the identity element of a group in which the operation is addition. (of a function, especially of a function of a complex variable) a point at which a given function, usually a function of a complex variable, has the value zero; a root.
Mucosa buccalis. The inner lining of the cheeks and lips, which is an anatomic region that includes all the mucous membrane lining of the inner surface of the cheeks and lips, from the line of contact of the opposing lips to the line of attachment of mucosa to the alveolar ridges and pterygomandibular raphe, which occupies an area of 50â60 cm2.
The mucosa serves to line the cavity of the tract. The mucosa consists of three sub-layers called the epithelium, the lamina propria, and the muscularis mucosae. In most of the digestive tract, the cells in the epithelium are shaped like columns.his mucus lubricates the digestive tract. The lamina propia is a sub-layer that is made of loose connective tissue. The muscularis mucosae is a sub-layer of smooth muscle. The next layer after the mucosa is called the submucosa. This layer is a thick layer of loose connective tissue.