Title: 10 Facts About the Digestive System
Headings: Anatomy & Physiology of Digestion: 10 Facts That Explain How the Body Absorbs Nutrients
Anatomy & Physiology of Digestion: 10 Facts That Explain How the Body Absorbs Nutrients
Small Intestine
1. Digestion Breaks Down Food to Give the Body Energy
2. Digestion Is a 6-Step Process
3. Structures of the Alimentary Canal Ingest Food and Propel It on a Journey Through the Body
4. The Layers of the Stomach Wall Help It to Churn, Expand, and Contract
5. The Autonomic Nervous System Plays a Key Role in Digestion
6. The Pharynx Is a Multitasker
7. The Small Intestine Has Three Regions
8. The Duodenum Is a Receptacle for Digestive Fluids
9. The Large Intestine Has 8 Regions
10. Digestive Juices Chemically Break Down Food
External Sources

Content: It has three muscle layers. The longitudinal and circular layers are found throughout the alimentary canal and move food along using peristaltic contractions. The third, oblique, layer in the stomach churns food to break it down. When all three stomach layers are in motion, the two openings (sphincters) are closed to keep food in the stomach. The stomach wall also includes rugae, which are folds that allow the stomach to expand as food enters. 5. The Autonomic Nervous System Plays a Key Role in Digestion
The autonomic nervous system controls peristalsis, the contraction and relaxation of muscle layers within the alimentary canal wall. Peristalsis is a key function in digestion; it literally gets the ball rolling. These involuntary contractions push swallowed food down the esophagus, churn the stomach, and propel chyme through the small intestine and large intestine.