Mucus

Secretion produced by mucous membranes

Mucus (MEW-kəs) is a slippery gel produced by, and covering, mucous membranes. Mucus forms a protective barrier between epithelial cells on the internal and external surfaces of the body and the outside environment. Mucus is found in the linings of the respiratory, digestive, and urogenital systems, and in the eyes and ears.

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