1. Gastrointestinal SystemPhysiology Review

2. The Job of the Bowel Food: Movement Breakdown Absorption Keeping dangerous gut contents out of the blood Keeping blood contents from being lost into the gutlumen 3. 4. Bowel and Mesenteries 5. QuestionTell whether the following statement is true orfalse.The mesentery contains the intestines bloodsupply. 6. TrueAnswerAn extension of the visceral peritoneum, themesentery contains blood vessels that supplyoxygen and nutrients to (arteries) andeliminate CO2 and waste from (veins) theintestines. 7. Prader-Willi Syndrome Plasma ghrelin levels are extremely highDiscussion: What are the effects of this disorder? 8. ScenarioA woman has a pancreatic tumor that secretesgastrin.Question What complication is likely to develop? Why? 9. Scenario A man cannot produce cholecystokinin.Question What problems will this cause him? 10. Carbohydrate Digestion Mouth: Salivary amylase Duodenum: pancreatic amylase Polysaccharides disaccharides Brush border enzymes Disaccharides monosaccharides Monsaccharides absorbed into blood 11. Protein Digestion Stomach: pepsinogen Activated to pepsin by acid in stomach Breaks proteins into polypeptides Duodenum: pancreatic trypsinogen Activated to trypsin in duodenum Breaks proteins into polypeptides Brush border enzymes Breaks polypeptides into 23 amino acid peptides Peptides absorbed into blood 12. Duodenum: bileFat Digestion Emulsifies fats Duodenum: pancreatic lipase Breaks triglycerides into glycerol and fatty acids Jejunum Packages digested fats as chylomicrons Passed to the lymph 13. QuestionDigestion of which substance begins in the mouth?b. Carbohydratesc. Proteind. Fate. All of the above 14. a. Carbohydrates AnswerCarbohydrate digestion begins in the mouth with salivary amylase; protein digestion begins in the stomach with pepsinogen; fat digestion begins in the small intestine with bile and pancreatic lipase. 15. DiscussionWhich is the best choice to reduce fat digestion? Suppress duodenal hormone secretion Suppress the activity of chief cells in the stomach Decrease intrinsic factor secretion Block gall bladder contraction Inactivate pancreatic lipase 16. QuestionHow would fat digestion be affected if bile levels decreased?b. It would increase.c. It would decrease.d. It would have no effectfat digestion is mainly affected by amylase.e. It would have no effectfat digestion is mainly affected by lipase. 17. Answera. It would decrease.Bile emulsifies fat so that it can be more easily digested. Decreased amounts of bile would lead to decreased fat emulsification and decreased ability to break down/digest fats.