1. Human Body
Digestive System

2. Functions Break down food (digest) Take in food (ingest)
Absorb nutrients from food
Eliminate (get rid of) solid waste

3. DIGESTION
The process of breaking down food into a form that the body can use
Large molecules into smaller ones!

4. Mechanical and Chemical
2 Types of digestion
Mechanical
and Chemical

5. Mechanical Digestion
Food is chewed, mixed and churned. Takes place in the mouth and stomach

6. Chemical Digestion
Chemical reactions that break down large molecules into smaller molecules that can be absorbed by cells
Examples: saliva in mouth acids & enzymes

7. ORGANS
Major Organs: Mouth Esophagus Stomach Small Intestine Large Intestine Rectum Anus
Accessory Organs:
Tongue
Teeth
Salivary Glands
Liver
Gallbladder
Pancreas

8. Mouth 1. Digestion begins
2. Mechanical (teeth and tongue) & Chemical (saliva) digestion
3. Saliva mixes with food to produce a soft mass called a Bolus

9. Esophagus 1. No digestion takes place
2. Peristalsis-muscle contractions (squeezing) that helps move food down the esophagus and through the digestive tract

10. Stomach 2. Produces HCl (hydrochloric acid) and mucus
1. Mechanical (churning) and chemical digestion
2. Produces HCl (hydrochloric acid) and mucus
3. Becomes a substance
called chyme (kime),
A thin watery product

11. Small Intestine
1. Major portion of all digestion occurs in the duodenum
2. Digestive juices from the liver, gall bladder (bile) and pancreas are added
3. Villi-make the surface larger so there are more places for food and nutrients to be absorbed

12. VILLI
Real above
Scientific illustration right

13. Large Intestine
1. Absorbs water from the chyme
2. Chyme may stay in the large intestine for up to 3 days

14. Rectum and Anus
Chyme makes its way out of the body, usually as “solid” waste… compacted in the rectum and expelled from the anus.