{ Functions of Digestive System

 Labeling Exercise Do Now

Review  Digestion using enzymes  Main site of absorption of nutrients  Includes  Duodenum  Jejunum  Ileum  Don’t get punched in the jejunum…  _ko _ko _ko

Small Intestines  Approximately 3 meters long  Numerous projections called villi that function to increase surface area  Total surface area of square meters  Why is increased surface area important?

Large Intestines  Also called the colon  Colon cancer?  Receives approximately 10 liters of water per day  1.5 L from food  8.5 L is from secretions  Last major part of the digestive system  Function is to remove water from indigestible food, and then pass waste material from the body  Takes approx. 16 hours to finish digestion

Large Intestines  Also absorbs sodium and other ions  If water is not absorbed, diarrhea can result  Causes dehydration and ion loss

Polyps  Small growths in the lining of the colon (large intestines)  Cancerous (malignant) or benign  Benign?  Low-fat, high-fiber diets are recommended to protect against colon cancer

Liver  Important in metabolism, glycogen storage and detoxification  Many vital functions  Secretes bile  Cannot live without a liver

 Bile stored for too long in gallbladder results in gallstones  Much like kidney stones, they are sharp  Gallstones can create blockage, backing up bile in the liver and entering the blood stream  Jaundice results from backup of bile in the blood Gallstones

Jaundice

 Blockage can also result in hepatitis  Hepatitis?  Inflammation of the liver  Can also result from poor drinking water Gallstones

 Complete crossword puzzle  May need to use books Crossword

{ Function of Digestive System

 Ingestion  Propulsion  Mechanical Digestion  Chemical Digestion  Absorption  Defecation GI Processes

 Monosaccharides  Glucose  Fructose  Galactose  Disaccharides (double sugars)  Sucrose – table sugar  Lactose – milk sugar  Maltose  Polysaccharides  Starch  Cellulose – cannot break down; provide fiber for diet Carbohydrate Sugars

 Sphincters are circular muscles that help close off passages  Cardioesophageal Sphincter  Causes heartburn  Pyloric sphincter Heartburn