1. THE DIGESTIVE SYSTEM
SNC 2PI April 2011

2. The Digestive Tract one long tube
takes food in, digests it and excretes the remaining waste
one or two openings
Digestive system of an earthworm

3. Worm Dissection

4. Human Digestive Tract
the human digestive system is more complex, consisting of:
Mouth
Esophagus
Stomach
Small Intestine
Large Intestine
Anus

5. The Digestive System mouth esophagus liver stomach gall bladder
pancreas
large intestine
small intestine
appendix
rectum
anus

6. Mouth Starts the process of breaking down food in one of two ways:
Mechanically
teeth and tongue
Chemically
enzymes

7. Esophagus Muscular tube connecting the mouth to the stomach
consists of smooth muscle, meaning that they can contract and relax without conscious thought

8. Stomach Major function is to hold and churn food
Lining has cells that produce digestive enzymes and acids
Smooth muscle contracts to mix contents
Rich in nerves to tell us when enough is enough

9. Small Intestine
many fine blood vessels that allow nutrients into the blood stream
Smooth muscles contract and relax to move food along
6 metres long and narrower than large intestine
Food stays in your small intestine for 4 to 8 hours

10. Large Intestine
1.5 metres in length and larger in diameter than small intestine
Absorbs water from the indigestible foods
Remaining solid matter is eliminated from the anus
Waste stays for 10 to 12 hours

11. Interesting Facts
Food is in your digestive system for about 24 hours

12. Your stomach stretches when you eat like a balloon being filled with air

13. You have a trap door called the epiglottis to cover your windpipe when you swallow.

14. The liver can completely regrow from a tiny piece

15. 1.7 litres of saliva is produced each day

16. Most of us pass somewhere between 200 and 2,000 ml of gas per day (average, about 600 ml) in roughly passages

17. Digestive System Video
Pg. 82 #2-5