All are true about 1st pa of duodenum, except ?

Ans. is 'd' i.e., Supplied by superior mesenteric aeryDuodenum Duodenum is 'C' shaped, shoest, widest and most fixed pa of small intestine. It is 25 cm long. It is devoid of mesentery. Most of the duodenum is retroperitoneal and fixed, except at its two ends where it is suspended by folds of peritoneum, and is therefore mobile. Duodenum lies opposite Ll, L2 and L3 veebrae.Duodenum is C-shaped curve which encloses the head of pancreas and is subdivided into four pas :1. First pa (Superior pa) : It is 5 cm (2 inches) long. It begins at the pylorus and meet the second pa at superior duodenal flexure. This pa appears as duodenal cap on barium studies.2. Second pa (Descending pa) : It is about 7.5 cm (3 inches) long. It is veical pa which begins at superior duodenal flexure and meet the third pa at inferior duodenal flexure. The interior of second pa of duodenum shows following features :i) Major duodenal papilla : It is present 8-10 cm distal to the pylorus. The hepatopancreatic ampulla or ampulla of Vater (joint pa of bile duct and pancreatic duct) opens here.ii) Minor duodenal papilla : It is present 6-8 cm distal to the pylorus. Accessory pancreatic duct opens here.3. Third pa (Horizonal pa) : It is 10 cm (4 inches) long. It begins at inferior duodenal flexure and passes towards the left in front of IVC behind superior mesenteric vessels and root of mesentery to meet 4th pa of duodenum.Fouh pa : It is 2-5 cm (1 inches) long and runs upward immediately to the left of aoa. It ends at duodenojejunal flexure by joining the jejunum.Aerial supplyThe pa of duodenum before the opening of bile duct (major duodenal papilla) develops from foregut and therefore is supplied by coeliac trunk through superior pancreaticoduodenal aery, a branch of gastroduodenal aery, which in trun is a branch of common hepatic aery. Pa of duodenum distal to opening of bile duct is developed from midgut and therefore is supplied by superior mesenteric aery through inferior pancreaticoduodenal aery. First pa of duodenum receives additional supply from right gastric aery, supraduodenal aery (a branch of common hapatic aery), retroduodenal branch of gastrodudenal aery and right gastropiploic aery.