Notes on the main parts of small intestine
The small intestine is a folded tube extending from the pyloric region of the stomach to the ileocaecal valve where it joins the large intestine. It is about 5 meters long and is made up of three parts. Duodenum, Jejunum and Ileum. The Duodenum is the first part of the small intestine. It is about 25 to 30 cms in length and lies in a C shaped fashion around the head of the pancreas.
About half way along, the concave surface of the Duodenum, the bile duct and the pancreatic duct enter the duodenal cavity together as a small papilla called the ampulla of vater. The Jejunum forms 2/5ths of the small intestine while the Ileum constitutes the rest of it. There is very little distinction between Jejunum and
Ileum as the former imperceptibly merges into the later. Both the jejunum and the ileum lay coiled in the central and lower abdominal cavity below the liver and the stomach.