Layers of the Alimentary Canal

The mucosa is the innermost layer of the gastrointestinal (GI) tract, composed of simple epithelium cells. It is the absorptive and secretory layer of the GI tract.

The submucosa is a dense irregular layer of connective tissue with large blood vessels, lymphatics, and nerves that supports the mucosa.

The muscularis is responsible for segmental contractions and peristaltic movement in the gastrointestinal (GI) tract.

Serosa consists of a secretory epithelial layer and a thin connective tissue layer that reduce the friction from muscle movement.