Submucosal glands can refer to various racemose exocrine glands of the mucous type. These glands secrete mucus to facilitate the movement of particles along the body's various tubes, such as the throat and intestines. The mucosa is the lining of the tubes, like a kind of skin. Submucosal means that the actual gland resides in the connecting tissue below the mucosa. The submucosa is the tissue that connects the mucosa to the muscle outside the tube.