Stomach

Chyme

Acidic, soupy, pasty mix of semidigested food in the stomach.

Cardiac Region

Small area of the stomach close to the cardiac orifice where the esophagus enters.

Fundic Region/Fundus

Dome-shaped superior part of the stomach above the esophageal attachment.

Body of the Stomach

Largest part of the stomach, distal to the cardiac orifice.

Pyloric Part

Narrow pouch at the inferior end of the stomach, subdivided into antrum and pyloric canal.

Pylorus

Part of the stomach that connects the pyloric canal to the duodenum, surrounded by the pyloric sphincter.

Pyloric Sphincter

Thick smooth muscle ring that regulates the passage of chyme into the duodenum.

Gastric Rugae

Longitudinal wrinkles formed in the stomach when empty.

Gastric Juices

Glands produce about 2 to 3 L of gastric juice daily, primarily water, hydrochloric acid, and pepsin.

Pepsinogen

A zymogen secreted by chief cells that is converted to active pepsin by hydrochloric acid.

Intrinsic Factor

A glycoprotein secreted by parietal cells, essential for the absorption of vitamin B12 in the small intestine.

Gastrin

Hormone produced by enteroendocrine G cells that stimulates secretion of hydrochloric acid and intrinsic factor.

Enterogastric Reflex

A neural response that inhibits gastric motility and secretion when the duodenum is distended or acidic.

Gastric Lipase

An enzyme secreted by chief cells in the stomach that digests 10% to 15% of dietary fats.

Neuroendocrine Cells

Cells that produce hormones and paracrine signals to regulate gastrointestinal function.

Zymogens

Inactive proteins that are converted to active enzymes by removing some amino acids.

Regenerative Stem Cells

Cells in the gastric pits that divide rapidly to replace dead cells in the gastric glands.