Duodenum 4 parts:
- Wraps around head of pancreas
- Supplied by Celiac trunk, SMA, sup, mid & inferior pancreaticoduodenal artery
1st part - superior
- only intraperitoneal part
- hepatoduodenal ligament + greater omentum attachment
2nd part - descending
- contains major (+ minor) duodenal papilla
- hepatopancreatic sphincter
3rd part - transverse, 4th ascending
- 4th part forms duodenojejunal flexure
- this flexure attachment to the posterior abdominal wall via ligament of Treitz
Jejunum
- entirely intraperitoneal
- no clear line between jej. + ileum ~2/3 of continuem
- lots of branches of SMA
- wall of jejunum is thicker and lumen wider
- jejunum contains more prominent circular folds of Kerckring
Ileum
- Longest part
- Form ileoceal function, laminar musculum of ileum protrudes to form fold
- SMA supply too
