Title: Small intestine: Anatomy, location and function | Kenhub
Headings: Small intestine
Small intestine: want to learn more about it?
Small intestine
Contents
Anatomy
Duodenum
Jejunum
Ileum
Histology
Function
Blood vessels
Innervation
Clinical relations
Duodenal ulcer
Small intestine: want to learn more about it?

Content: vagus nerve (CN X) (through the submucosal (Meissner’s) and myenteric (Auerbach’s) nervous plexuses)
Sympathetic: Thoracic splanchnic nerves
Function
Final stages of food digestion
Absorption of nutrients and water
Clinical relations
Diarrhea, obstructive disorders, infectious diseases, neoplastic growths, congenital conditions, duodenal ulcer
Contents
Anatomy
Duodenum
Jejunum
Ileum
Histology
Function
Blood vessels
Innervation
Clinical relations
Duodenal ulcer
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Anatomy
The small intestine is divided into the duodenum, jejunum, and ileum. Together these can extend up to six meters in length. All three parts are covered with the greater omentum anteriorly. The duodenum has both intraperitoneal and retroperitoneal parts, while the jejunum and ileum are entirely intraperitoneal organs. As the small intestine is the main site for the final stages of food digestion and its absorption, its gross and microanatomy are adjusted to that function. Duodenum
The duodenum by definition is the first part of the small intestine. It extends from the pyloric sphincter of the stomach, wraps around the head of the pancreas in a C-shape and ends at duodenojejunal flexure. This flexure is attached to the posterior abdominal wall by a peritoneal fold called the suspensory muscle (ligament) of duodenum, also called the ligament of Treitz . Duodenum
The duodenum has four parts: