2. 1 By Rebecca K. Fraker

3. 2 Introduction The digestive system is used for breaking down food into nutrients which then pass into the circulatory system and are taken to where they are needed in the body.

4. 3 Introduction There are four stages to food processing: 1.Ingestion: taking in food 2.Digestion: breaking down food into nutrients 3.Absorption: taking in nutrients by cells 4.Egestion: removing any leftover wastes

5. 4 The Digestive System Esophagus Stomach Small Intestine Large Intestine Liver Gall Bladder Pancreas What has happened to the food you ate today?

6. 5 In the Mouth Digestion actually begins in the mouth. The teeth break the food into smaller pieces, and the tongue moves the pieces around so that saliva can be mixed with them. This begins the digestion. Then swallow, and the journey begins!

7. 6 The Human Digestive System The tongue moves the food around until it forms a ball called a bolus. The bolus is passed to the pharynx (throat) and the epiglottis makes sure the bolus passes into the esophagus and not down the windpipe!

8. 7 Esophagus About 10” long Moves food from the throat to the stomach. –The muscle movement is called peristalsis. Heartburn is when acid from the stomach gets in here.

9. 8 Stomach Stores the food you eat, breaks it down into tiny pieces. Mixes food with digestive juices. Acid in the stomach kills bacteria. It can stretch and shrink.

10. 9 Small Intestine Small intestines are roughly 22 feet long. “Small” refers to its diameter, not its length. Insides are coated with little ‘fingers’ called villi to increase surface area. Nutrients from the food pass into the bloodstream through the small intestine walls. You can have pieces removed but it is very hard for your body to get the right nutrients.

11. 10 Villi

12. 11 Large Intestine About 5 feet long. Accepts what small intestines don’t absorb. Absorbs water and minerals from the waste matter. You can lose a large part of this and still survive.

13. 12 Liver Directly affects digestion by producing bile. –Bile helps digest fat. Processes nutrients in the blood, filters out toxins and waste. Is often called the body’s energy factory. You cannot live without a liver, although you can live with a part of one. Drinking alcohol damages the liver.

14. 13 Gall Bladder Stores bile from the liver. Delivers bile when food is digested. Fatty diets can cause gallstones. You can live without a gallbladder.

15. 14 Pancreas Produces compounds to digest fats and proteins. Neutralizes acids that enter small intestine. Regulates blood sugar by producing insulin. If it doesn’t work right you get diabetes.

16. 15 Fun Facts HOW LONG ARE YOUR INTESTINES? At least 25 feet in an adult. Be glad you're not a full-grown horse -- their coiled-up intestines are 89 feet long! Food drying up and hanging out in the large intestine can last 18 hours to 2 days! In your lifetime, your digestive system may handle about 50 tons!!

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18. 17 On a sheet of paper, write the name of each colored organ: Green: Red: Pink: Brown: Purple: Green: Yellow:

19. 18 Did you get the answers right? Green: Esophagus Red: Stomach Pink: Small Intestine Brown: Large Intestine Purple: Liver Green: Gall Bladder Yellow: Pancreas Great Job!

20. 19 References and Links Your Digestive System and How It Works: http://digestive.niddk.nih.gov/ddiseases/pubs/yrdd/Your_Digestive_Sys.pdf –Digestive system diagram comes from this site The Real Deal on the Digestive System http://kidshealth.org/kid/body/digest_SW_p2.html Pancreas: Introduction and Index http://www.vivo.colostate.edu/hbooks/pathphys/digestion/pancreas/i ndex.html Your Gross and Cool Body – Digestive System http://yucky.discovery.com/flash/body/pg000126.html