1. Unit 2: Internal Systems The Digestive System

2. Digestive System responsible for 4 major functions: 1. ingestion intake of nutrients (eating) 2. digestion the breakdown of food into small soluble molecules a) physical digestion: (ex.) chewing mechanical digestion that cuts food into small pieces smaller pieces increase surface area for enzymes to work on

3. Digestive System 4 major functions (continued): b) chemical digestion: ex. digestive secretions (saliva) enzymes in digestive juices chemically breakdown food molecules into their monomers (soluble) monomersfood

4. Digestive System b) chemical digestion: (continued) i) carbohydrates i.e. polysaccharides & disaccharides monosaccharides

5. Digestive System b) chemical digestion (continued): ii) proteins amino acids

6. Digestive System b) chemical digestion (continued): iii) lipids

7. Digestive System 4 major functions (continued): 3. absorption digested nutrients (soluble) absorbed into blood stream or lymphatic system 4. Egestion: removal of solid undigested material (feces) from anus  eating cellulose (fiber) helps ** Excretion (part of the excretory system) removal of liquid soluble waste (urine) from the bladder via urethra

8. Components of the Digestive System Mouth Esophagus Stomach Small Intestine Large Intestine Rectum Anus Liver Pancreas Gall Bladder digestive tract (alimentary canal) really just a very long tube (~ 9 m long) takes food ~ 24 - 33 hours to go through digestive tract

9. Homework 1. Digestive System Cut Out – start in class 2. “Taking A Look At The Mouth “ label & fill in the missing information will be taken up tomorrow