False-colour scanning electron micrograph (SEM) of the glandular lining of the stomach. The gastric mucosa is the site of production of hydrochloric acid, digestive enzymes, hormones and mucous. The surface epithelium of simple columnar cells (seen here), secretes mucous. While gastric glands occur as downgrowths of this epithelium, forming pits. From these pits digestive enzymes are produced. The stomach acts to churn food around while gastric juices act to chemically break the food down. A thick lining to the stomach and copious amounts of mucous protect it from these digestive processes. Magnification: x550 at 6x7cm size. Magnification: x875 at 4x5 inch size.