fundus

Meaning: The stomach is divided into the cardia (the entry from the esophagus), the fundus, the body, and the pylorus (antrum plus pyloric sphincter). The fundus is the rounded top that bulges above the cardia. It holds swallowed food and gas, and the wall relaxes to accommodate it. Gastric glands in the fundus and body contain parietal cells (HCl and intrinsic factor), chief cells (pepsinogen) and mucous cells. Gastrin-secreting G cells are found mainly in the antrum. In general anatomy, a fundus is the part of a hollow organ opposite its opening. The uterine fundus is the rounded top above the openings of the fallopian tubes.

On the MCAT: A digestion passage asks where a secretion comes from, or what follows if one cell type is blocked or lost. Predict the direction of the change. Less parietal cell activity means higher gastric pH, less conversion of pepsinogen to pepsin (which needs low pH), and less intrinsic factor, so poorer vitamin B12 absorption in the ileum.

Common confusion: Students link fundus with "bottom" because the Latin word means base. The base is relative to the opening, so in the upright stomach the fundus is the upper part, and the pylorus is the lower exit. Also keep the cell locations separate. HCl comes from parietal cells in the fundus and body, while gastrin comes mainly from antral G cells. Gastrin then stimulates the parietal cells.