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Small Intestine

By

The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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Your digestive tract (also called the gastrointestinal or GI tract) is the hollow tube that food goes through when you swallow it, digest it, and then pass the waste products as stool.

What is the small intestine?

Your small intestine has three parts:

  • Duodenum

  • Jejunum

  • Ileum

The duodenum is the first part of your small intestine and is connected to your stomach. Food and liquid leave your stomach and go into your duodenum to continue being digested. Digestive juices from your pancreas Pancreas Your digestive system breaks food down into separate nutrients that fuel your body. It includes your digestive tract plus organs that lie outside the digestive tract but help with digestion... read more and bile (a green fluid that helps digest fat) from your gallbladder Gallbladder Your gallbladder is a small sac located on the right side of your belly just below your ribs. It's the organ where your body stores bile before it goes into your intestine. Bile is a digestive... read more come into your duodenum through small tubes called ducts. These juices help break down food and also neutralize stomach acid. The walls of the small intestine make chemicals called enzymes that also help digest food.

The jejunum and ileum are the 2nd and 3rd parts of the small intestine. They absorb nutrients.

The walls of the small intestine are lined with muscles that contract to push food along.

Locating the Small Intestine

Locating the Small Intestine
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