Layers of the stomach wall @(Model.HeadingTag)>
The stomach is made up of several layers of tissue:
- The mucosa (mucous membrane) is the inner lining of the stomach. It is made up of
glandsand specialized cells that make mucus, hydrochloric acid and enzymes. The mucosa has ridges (rugae) when the stomach is empty. The ridges flatten out as the stomach fills with food.
- The submucosa is a layer of connective tissue that surrounds the mucosa. It contains larger blood and lymph vessels, nerve cells and fibres.
- The muscularis propria (muscularis externa) is the next layer that covers the submucosa. It is the main muscle of the stomach and is made up of 2 layers of muscle.
- The serosa is the fibrous membrane that covers the outside of the stomach. The serosa of the stomach is also called the
How the stomach works @(Model.HeadingTag)>
When you see, smell or think of food, your central nervous system (CNS) sends a message to your stomach to make acids, enzymes and mucus for digestion (called gastric juice). Endocrine cells in the stomach release the
After food and liquids are swallowed, they travel through the esophagus to the stomach. The muscles of the stomach wall tighten (contract) and relax (expand), which mixes the food with the acids and enzymes. Mucus helps protect the lining of the stomach from the acids.
Food and liquids are broken down into a thick, acidic, soupy mixture called chyme. Once chyme is formed, the pyloric sphincter relaxes. Then the stomach muscles tighten and relax to help move the chyme into the duodenum where digestion continues and many nutrients are absorbed (taken up).
The stomach does not have a big role in absorption of food. It absorbs only water, alcohol and some drugs.
Ashley Stueck, MD, FRCPC
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Surveillance, Epidemiology and End Results (SEER) Program . SEER Training Modules: Stomach . Bethesda, MD: National Cancer Institute; https://training.seer.cancer.gov/. Thursday, January 31, 2019.