Understanding the Human Digestive System: Key Parts & Functions

Mouth

- Lips: form the opening of the mouth

- Tongue: mixes saliva with food, aids in swallowing

- Teeth: break food into smaller pieces

- Salivary glands: produce saliva, which contains enzymes that begin to break down carbohydrates

Esophagus

- Muscular tube that connects the mouth to the stomach

- Transports food through peristaltic contractions

Stomach

- J-shaped organ that stores and churns food

- Produces gastric juice, which contains enzymes and acid that further break down food

- Begins to absorb water and electrolytes

Small intestine

- Long, coiled tube that is the main site of digestion and absorption

- Subdivided into three sections: duodenum, jejunum, and ileum

- Receives bile from the liver and pancreatic juice from the pancreas, which help break down food further

- Absorbs nutrients into the bloodstream

Large intestine (colon)

- Absorbs water and electrolytes from undigested food

- Stores waste until it is eliminated

Rectum

- Stores solid waste until it is eliminated

Anus

- Muscular opening through which solid waste is eliminated