1. Mouth

Teeth: Break down food into smaller pieces through chewing.

Salivary Glands: Produce saliva, which contains enzymes like amylase that begin breaking down carbohydrates.

Tongue: Helps move food around and forms it into a bolus (a small ball) for swallowing.

2. Pharynx and Esophagus

Pharynx (Throat): A pathway for the movement of food from the mouth to the esophagus.

Esophagus: A muscular tube that transports food from the pharynx to the stomach through a series of coordinated muscle contractions called peristalsis.

3. Stomach

Gastric Juices: The stomach secretes hydrochloric acid (HCl) and digestive enzymes like pepsin that help break down proteins.

Churning: The stomach muscles mix food with digestive juices, turning it into a semi-liquid substance called chyme.

4. Small Intestine

Duodenum: The first section where chyme mixes with bile (from the liver) and pancreatic enzymes to continue digestion.

Jejunum and Ileum: Where the majority of nutrient absorption occurs. The walls of the small intestine are lined with villi, small finger-like projections that increase surface area for absorption.

5. Pancreas, Liver, and Gallbladder

Pancreas: Produces digestive enzymes and bicarbonate to neutralize stomach acid.

Liver: Produces bile, which helps digest fats.

Gallbladder: Stores bile produced by the liver and releases it into the small intestine as needed.

6. Large Intestine (Colon)

Absorption of Water: The large intestine absorbs water and salts from the remaining indigestible food matter.

Formation of Feces: The remaining waste material is formed into feces.

7. Rectum and Anus

Rectum: Stores feces until they are ready to be expelled.

Anus: The opening through which feces are expelled from the body.

8. Accessory Organs

Appendix: A small tube attached to the large intestine with a debated function, possibly related to the immune system.

Summary of the Digestive Process:

Ingestion: Food enters the mouth.

Digestion: Mechanical and chemical breakdown of food.

Absorption: Nutrients and water are absorbed in the small and large intestines.

Elimination: Waste is expelled as feces.

This system ensures that the body receives the nutrients it needs to function properly.

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