Which statement best completes this sentence The superior mesenteric aery:

The superior mesenteric aery arises from the aoa at the level of L1 and then descends. It then passes behind the splenic vein and the body of the pancreas. The superior mesenteric aery is the aery of the midgut, and supplies the duodenum, small intestine and the large intestine as far as a point 2/3 of the way along the transverse colon. The superior mesenteric aery passes anterior to the uncinate process of the pancreas and the left renal vein. The superior mesenteric vessels cross the third pa of the duodenum after passing over the uncinate process of the pancreas.