Definition

Anatomy of the Digestive System

Choose a preferred language

Food gives the body the energy needed for life. The digestive system breaks food down into basic nutrients that can be used by the body. The digestive tract is a long, muscular tube that extends from the mouth through the stomach and intestines to the anus. As food moves along the digestive tract, it's digested. This means it's changed into substances that can be absorbed into the bloodstream. Certain organs (such as the liver, gallbladder, and pancreas) help with this digestion. Parts of food that can't be digested are turned into stool. This is waste material that's passed out of the body.


Digestive system

Outline of man showing gastrointestinal system.

The digestive system is made up of the following:

  • The mouth. Takes in food, breaks it into pieces, and begins the digestion process.

  • The esophagus. Moves food from the mouth to the stomach.

  • Thestomach. Breaks food down into a liquid mixture.

  • Theliver. Makes bile that helps digest fat, removes toxins from blood, and maintains healthy blood sugar levels.

  • The gallbladder. Stores, concentrates, and controls the flow of bile into the small intestine.

  • Thepancreas. Makes enzymes that help in digestion. And makes hormones that help control blood sugar.

  • Thesmall intestine. Digests food further. And absorbs nutrients and water from food so they can be used by the body. What's left is passed on to the colon as liquid waste.

  • The large intestine (colon). Absorbs water, salt, and minerals from the waste, forming a solid stool.

  • The rectum. Stores stool until a bowel movement happens.

  • Theanus. The opening where stool leaves the body.

© 2000-2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

Find the right providers for your needs.

CalOptima Health works with thousands of Orange County providers, including doctors, specialists, health networks, medical groups and more.

Find a Doctor

Get Care Now

Your health is everything to us. Please reach out for support if you need it.

Get Care Now
Related Articles
Read article
Digestive Health
The Digestive System: An Overview

Detailed information on how the digestive system works, including a full-color, labeled illustration of the digestive system.

Read article
Digestive Health
The Pancreas: Anatomy and Functions

Detailed anatomical description of human pancreas, including simple definitions and labeled, full-color illustrations

Read article
Digestive Health
How the Liver Works

Detailed information on how the liver works, including a full-color, labeled illustration of the digestive system

Read article
Digestive Health
Anatomy of the Anus

The anus is the last part of the digestive tract. Learn more about its anatomy, including where anal cancer is likely to start.