Transcript Functions

Human Anatomy and
Physiology
An overview of digestion
Anatomy overview
Functions
1. Ingestion – mouth
2. Motility
• Maintain muscle tone
• A. Propulsive movement: unidirectional
• esophagus, large intestine
• B. Mixing movement: bidirectional
• stomach, small intestine
Functions
3. Digestion
• Mechanical
Mouth (chewing), stomach (churning), small intestine
(segmentation)
• Chemical
Passage across plasma membranes
Carbohydrates: tri-, disaccharides to monoProteins: into amino acids
Fats: monoglycerides and fatty acids
Functions
4. Secretion
Mouth, stomach, liver, pancreas, small intestine
5. Absorption
80% in the duodenum, rest in small and large intestine
6. Elimination of wastes
Small intestine anatomy
1
2
3
4
Absorption
Intestinal villi and microvilli
Absorption through villi
Esophagus
Stomach
Absorption through villi
Small intestine
Absorption through villi
Large intestine
Accessory glands
• Salivary glands
• Moisten, lubricate, breakdown saccharides
• Pancreas
• Enzymes secreted into duodenum, neutralizes stomach
acid
• Liver
• Breakdown fats, neutralizes stomach acid
• Gall bladder
• Store bile made by the liver