1. The Esophagus Long tube Epiglottis Peristalsis Lower esophageal sphincter Heartburn Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Bolus of food Tongue Epiglottis Larnyx Trachea (a) (b) Esophagus (c)

2. The Stomach Sphincters Size Gastric juices Holding “tank” Formation of chyme Prevention of autodigestion

3. Physiology of the Stomach

4. Stomach Acid Destroys activity of protein Activates digestive enzymes Partially digests dietary protein Assists in calcium absorption Makes dietary minerals soluble for absorption

5. Peristalsis

6. The Small Intestine Approximately 10 feet long Folded walls Villi Absorptive cells Rapid cell turnover

7. The Small Intestine

8. Nutrient Absorption Passive absorption Facilitated absorption Active absorption Phagocytosis and pinocytosis

9. Nutrient Absorption

10. The Large Intestine Indigestible food stuff No villi or enzymes Mucus-producing cells Absorption of water, some minerals, vitamins Bacteria –Probiotics –Prebiotics Elimination

12. Rectum Stool Elimination Muscle contraction Anal sphincters

13. Accessory Organs Pancreas Gallbladder Liver

14. The Liver Bile Gallbladder Enterohepatic circulation

15. The Pancreas Digestive enzymes Hormones –Glucagon and insulin Pancreatic juices –Bicarbonate

16. The Urinary System Kidneys Ureter Bladder Urethra Waste products Blood acid-base balance (pH)

17. Basic Renal Processes Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode (Slide Show view). You may see blank slides in the “Normal” or “Slide Sorter” views. All animations will appear after viewing in Presentation Mode and playing each animation. Most animations will require the latest version of the Flash Player, which is available at http://get.adobe.com/flashplayer.

18. Nutrient Storage Capabilities Maintaining reserves Adipose tissue Glucose Amino acids Vitamins and minerals –Calcium in bones

19. Nutrition and Genetics Nutrigenomics Nutritional diseases with a genetic link –Cardiovascular disease –Obesity –Diabetes –Cancer

20. Common Problems with Digestion Ulcers Heartburn Constipation Hemorrhoids Irritable Bowel Syndrome Diarrhea Gallstones

21. Ulcers Can occur in esophagus, stomach and small intestine Cause –H. Pylori –NSAIDS

22. Ulcers

24. Heartburn

25. Gastroesophageal reflux disease (GERD)

26. Constipation Difficult or infrequent evacuation Causes –Ignoring normal urges –Muscle spasms –Certain medications Treatment –Dietary fiber –Fluids –Regular physical activity

27. Laxatives Irritate the intestinal nerve Draw water into the intestine Regular use is harmful

28. Hemorrhoids (piles) Swollen veins of the rectum and anus Intense pressure and straining Dietary recommendation: –Fiber and fluid

29. Irritable Bowel Syndrome Symptoms –Cramps, bloating, increased frequency, diarrhea, constipation Causes –Altered intestinal peristalsis –Decreased pain threshold Individualized treatment –Elimination diet –Moderate caffeine –Low-fat, small, frequent meals –Stress reduction

30. Diarrhea Fluidity and frequency Causes –Infections –Poorly absorbed substances Treatment: –Plenty of fluid

31. Gallstones Symptoms –Upper right abdominal pain, gas, bloating, nausea and vomiting Treatment –Removal of gallbladder

32. Cystic Fibrosis Mucous blocks pancreatic ducts Impaired digestion of carbohydrates, protein and fat Treatment –Replacement enzymes

33. Celiac Disease Allergic reaction to gluten Flattens villi Limits absorption of nutrients Treatment –Elimination of wheat and rye