the parietal cells of the gastric mucosa secrete
Gastric mucosa There are three types of glands: cardiac glands (in the proximal part of the stomach), fundic (oxyntic) glands (the dominating type of gland), and pyloric glands. The cardiac glands mainly contain mucus-producing cells called foveolar cells. The bottom part of the oxyntic glands is dominated by zymogenic (chief) cells that produce pepsinogen (an inactive precursor of the pepsin enzyme). Parietal cells, which secrete hydrochloric acid (HCl) are scattered in the glands, with most of them in the middle part. The upper part of the glands consist of mucous neck cells; in this part the dividing cells are seen. The pyloric glands contain mucus-secreting cells.
Intestinal epithelium The intestinal epithelium is the layer of cells that forms the luminal surface or lining of both the small and large intestine (colon) of the gastrointestinal tract. It is composed of simple columnar epithelium. It has two important functions: absorbing helpful substances and providing a barrier against harmful substances. Some diseases and conditions are caused by dysfunction in the intestinal epithelium, and some diseases and conditions cause problems with these cells, which then leads to further complications.