What is the jejunum?
It is called the jejunum. Gray's Anatomy (1918) describes it as the middle segment of the small intestine.
What it is
- The middle segment of the small intestine.
- Has thicker walls and more prominent mucosal folds than the ileum.
- The main site of nutrient absorption.
Where it is
- Between the duodenum above and the ileum below.
- Occupies the upper left of the abdomen.
- About two-fifths of the small intestine below the duodenum.
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Last verified: 2026-07-18
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