Gastric gland: false-colour scanning electron micrograph (SEM) of the mucous membrane lining the stomach, showing the shadowy entrances to a number of gastric glands. The glands secrete gastric juice (hydrochloric acid & the enzyme pepsin) and a protective mucous, derived from the simple, columnar cells (moss-like) that comprise the mucosa. Gastric glands are formed by simple invagination or tubular ingrowth of this mucosa into the underlying layer of tissue, the lamina propria. Magnification: x300 at 6x7cm size.