THE DIGESTIVE SYSTEM SNC 2PI April 2011

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

Worm Dissection

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

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

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

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

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

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

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

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

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

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

The liver can completely regrow from a tiny piece

1.7 litres of saliva is produced each day

Most of us pass somewhere between 200 and 2,000 ml of gas per day (average, about 600 ml) in roughly 13-14 passages

Digestive System Video Pg. 82 #2-5