Chapter 15 Questions for Digestive System
1. What are the two major secretions of the stomach?
2. Which hormones promote the secretion of HCl?
3. Which hormones suppress the secretion of HCl?
4. Which hormones promote the secretion of pepsinogen?
5. How, where, and why does pepsinogen get converted to pepsin?
6. What is the function of HCl in the stomach?
7. What is the function of pepsin?
8. What is secreted by parietal cells?
9. What is secreted by chief cells?
10. In which segment of the digestive tract does most digestion (hydrolysis) and absorption
occur?
11. Name the enzymes or categories of enzymes responsible for the hydrolysis of
carbohydrates, proteins, fats, and nucleic acids.
12. Once carbohydrates, proteins, fats, and nucleic acids have been hydrolyzed, in what
forms are their breakdown products absorbed.
13. Where are most vitamins, minerals, and water absorbed?
14. What are the endocrine secretions of the pancreas?
15. What are the exocrine secretions of the pancreas?
16. What are the two major sources of bicarbonate ions that arrive in the duodenum?
17. What is the purpose of bicarbonate in the duodenum?
18. What hormones control the secretion of bicarbonate?
19. What is the composition of bile?
20. What are bile salts? What is their function?
21. What is the purpose and function of the gall bladder?
22. What hormone causes the gall bladder to contract?
23. What conditions trigger the secretion of the hormone that causes the gall bladder to
contract?
24. What is the sphincter of Oddi and which hormone causes it to relax?
25. How do amino acids and monosaccharides enter intestinal epithelial cells?
26. What are the major functions of the large intestine?
27. What happens to digestive enzymes that are secreted into the lumen of the digestive
tract?
28. What are some of the functions of the liver (see Table 15-2.)
29. What are the names of the four layers which comprise the gastrointestinal wall?
30. What is the enteric nervous system and what is its function?
31. What specializations in the small intestine maximize surface area for digestion and
absorption?
32. What is the location and function of a lacteal?
33. To which organ is most blood delivered once it leaves the digestive tract? Why should
blood be routed to this organ before entering the general circulation?
34. What is emulsification and why is this process necessary?
35. How are micelles formed? What comprises micelles?
36. How does the absorption of lipids differ from that of simple sugars and amino acids?
37. What are chylomicra and where to these structures form?
38. Explain how a quadriplegic can still digest and absorb meals even though there is no
anatomical connection between the brain and the organs of the gut.
39. For each of these hormones, state the organ of origin, the factors that stimulate their
secretion, their target cells and the actions on those target cells: Gastrin, CCK, Secretin,
and GIP.
40. What is enterokinase? Where is it located and why it is so important for the digestion of
proteins?