what does epithelial tissue do in the stomach
These folds give the stomach its well-known ability to enlarge when engorged with food. On the outermost layer of these folds you may see a thin line of material. This is mucus which helps protect the tissues below from the harsh environment of the stomach. The innermost layer is a lining of simple columnar epithelium (labeled in the high magnification image). This type of epithelium provides the greatest surface area for abosrption or secretion. In the stomach the epithelial cells exposed to the lumen are primarily constructed to resist digestion by the lumen contents. The epithelial layer forms depressions called gastric glands or pits. Within these pits are mucous secreting cells, parietal cells which secrete HCL, and chief cells which secrete pepsinogen.