Difference between revisions of "Jejunum - Anatomy & Physiology"
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*The cranial mesenteric vein drains blood from the jejunum and enters the portal vein. | *The cranial mesenteric vein drains blood from the jejunum and enters the portal vein. | ||
**It is rich in the products of digestion following a meal. | **It is rich in the products of digestion following a meal. | ||
− | **The portal vein enters the liver. | + | **The portal vein enters the [[Liver - Anatomy & Physiology|liver]]. |
==Innervation== | ==Innervation== |
Revision as of 14:55, 10 July 2008
Introduction
Structure
- The jejunum is the longest part of the small intestine.
- It is highly coiled and occupies the ventral part of the abdominal cavity, filling those parts that are not occupied by other viscera. This produces species variation (see comparative aspects).
- It is suspended by the mesentry (mesojejunum). This conveys the blood vessels and nerves and houses lymph nodes.
- The mesentry converges to its root. This is where the cranial mesenteric artery branches off from the aorta.
Function
- Has digestive and absorptive functions.
Vasculature
- The cranial mesenteric artery, a branch of the abdominal aorta, supplies blood to the jejunum, ileum, caecum, ascending colon and part of the transverse colon.
- It branches greatly within the mesenty of the jejunum.
- There are many anastomoses within the mesentry, which ensure that the intestine can survive even if a major division of the cranial mesenteric is damaged.
- The cranial mesenteric vein drains blood from the jejunum and enters the portal vein.
- It is rich in the products of digestion following a meal.
- The portal vein enters the liver.