Location and structure of the small intestine

Location and structure of the small intestine - the small intestine (intestinum tenue) is the longest part of the digestive tract (about 5-7 metres), located between the stomach and the large intestine, and is made up of three parts: the duodenum, jejunum and ileum.

with Small intestinefrom the inside outwards: the mucosa (made up of the absorbent epithelium, the submucosal connective tissue layer and the epithelium's own muscle layer), the submucosa (the connective tissue layer between the mucosal muscle layer and the true muscle layer, in which the Small intestineglands /Brunner's glands/), the muscle layer (inner circumferential and outer longitudinal) and the serosa (the peritoneal layer covering the small intestine).

This latter layer is absent in the initial part of the duodenum, where the horseshoe gut runs in the space behind the peritoneum.