Digestive System

Lower Gastrointestinal Tract

How is the small intestine divided into segments?

The small intestine is divided into three segments: 1) the duodenum, 2) the jejunum, and 3) the ileum. The duodenum is approximately 10 inches long (25 centimeters) and begins at the junction between the stomach and small intestine at the pyloric sphincter. The jejunum is about 8 feet (2.5 meters) long. The longest segment of the small intestine is the last segment, the ileum. It is 12 feet (3.5 meters) long. Each segment has the same basic anatomical structure and appearance.


This is a web preview of the "The Handy Anatomy Answer Book" app. Many features only work on your mobile device. If you like what you see, we hope you will consider buying. Get the App