Digestive System Review
1. Differentiate between physical and chemical digestion and state the function of each.
2. How are the two stages of digestion related?
3. Why are you able to swallow water while standing on your head?
4. How do the teeth and tongue function in digestion?
5. What is the purpose of saliva?
6. What prevents self-digestion of the stomach?
7. What is the combined effect of sphincter muscles and peristalsis in the stomach?
8. What would be the result if the stomach did not have sphincter muscles?
9. Why is surface area important in the small intestine and what features increase it?
10. You might say that the small intestine is the most important organ of the digestive system. Why might you be justified in saying so?
11. What happens to food molecules after being absorbed in the small intestine?
12. What’s the deal with pepsinogen and pepsin?
13. How is the small intestine protected from the acid chyme? From pepsin?
14. In cases of extreme obesity, surgical procedures can be used to control weight. For each, state the effect on the patient:
a) a section of the small intestine is removed.
b) the size of the stomach is reduced.
15. A person can live without a gallbladder but not without a liver. Explain.
16. If the gall bladder is removed, why is the common bile duct left intact?
17. Explain how the backwash of bile into the stomach can cause stomach ulcers.
18. The incidence of colon cancer is highest in countries where people eat the greatest quantities of animal fats and proteins. Individuals who live in countries where cereal grains form the basic diet have a much lower incidence of colon cancer. What conclusion might you draw from these data? Can colon cancer be eliminated by a change in diet?
19. If a person were suffering from gallstones, what foods might they have difficulty digesting?
20. Why might a person with an obstructed bile duct develop jaundice?
21. You have just eaten a cheese sandwich and for the next several hours your digestive system will go to work. Discuss what happens to the large food molecules as they are chemically broken down into nutrients. Finally, explain how these nutrients are absorbed into the bloodstream.
22. A man has high levels of cholesterol in his blood. What dietary recommendations would you give him?
23. What is a calorie?
What is a Calorie?24. What are the three types of large molecules we need in our diet?
25. What is the major source of starch in the North American diet?
Fats? Protein?26. What dietary purpose does fat serve?
27. Why is fat well-suited for its role?
28. Most plant proteins are incomplete. What must vegetarians do to ensure they get complete protein?
Complete the following table
Nutrient |
Digestion Begins |
Digestion Completed |
Carbohydrates |
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Proteins |
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Fats |
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Complete the following table
Organ |
Enzyme(s) |
Function of enzyme(s) |
Mouth |
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Stomach |
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Pancreas |
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Small Intestine |
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