mucous membrane

a moist MEMBRANE that lines many tubes and cavities within the body and is lubricated with MUCUS . The structure of a mucous membrane varies according to its site, and they are found, for example, lining the mouth, respiratory, urinary and digestive tracts. Each has a surface EPITHELIUM , a layer containing various cells and glands that secret mucus. Beneath this lie CONNECTIVE TISSUE and MUSCLE layers, the laminae propria and muscularis mucosa respectively, the whole forming a pliable layer.