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: Dysfunction of the small intestine can bring you some uneasy experiences such as diarrhea while travelling or worse, on a date. This article will discuss the anatomy, function and neurovasculature supply of the small intestines. Key facts about the small intestine
Definition
A part of the alimentary tract which extends from the stomach (pyloric orifice) to the large intestine (ileal orifice)
Parts
Duodenum, jejunum, ileum
Blood supply
Arteries: celiac trunk, superior mesenteric artery
Veins: hepatic portal vein, superior mesenteric vein
Innervation
Parasympathetic: 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
+ Show all
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.