1. Where/when does digestion begin?
c. Small intestine
d. Cephalic response
2. What structure prevents food from entering the trachea when you swallow?
3. Which large vessel is the first to receive most recently eaten nutrients, transporting them to the liver?
a. Portal vein
b. Mesenteric vein
c. Subclavian vein
d. Hepatic vein
4. Blood leaving the intestine goes by way of a vein to the:
5. After digestion and absorption, which circulatory system carries fat and fat-soluble vitamins?
6. Which of the following is a feature of the lymphatic system?
a. It is composed of a mucus-like substance
b. It picks-up and transports dietary lipids
c. It serves to transport fat and water-soluble vitamins to the heart
d. It funnels nutrients to the liver via a one-way pump
7. Which of the following is true about the lymphatic system?
a. The specialized fluid carried by this system is blood
b. This system never intersects with the bloodstream
c. It is not involved in the transport of nutrients
d. It is important for transporting fat-soluble nutrients
8. All the following are features of the epiglottis except it:
a. Covers the opening of the trachea
b. Prevents food from entering the windpipe during swallowing
c. Guides food down the esophagus
d. Is the first GI tract sphincter
9. Most digestion takes place in the:
b. Small intestine
d. Large intestine
10. The ring-like muscles that retard or prevent backflow of partially digested food in the gastrointestinal tract are called:
11. Which of the following is a function of sphincter muscles?
a. Breaks apart food particles
b. Controls passage of food through the GI tract
c. Controls peristalsis
d. Releases enzymes and hormones into the GI tract
12. What sphincter separates the small intestine from the large intestine?
13. What is the function of the pyloric sphincter?
a. Prevents esophageal contents from emptying too quickly into the stomach
b. Prevents stomach contents from backing up into the esophagus
c. Prevents intestinal contents from backing up into the stomach
d. Prevents intestinal contents from emptying too quickly into the colon
14. The stomach empties into the small intestine through the:
a. Pyloric sphincter
b. Esophageal sphincter
c. Sphincter of Oddi
d. Ileocecal sphincter
15. Which of the following is not a sphincter?
16. Which of the following is a description of chyme?
a. A watery mixture of partially digested food released by the stomach into the intestines
b. The semisolid mass of undigested food which is swallowed
c. The mixture of pancreatic juices containing enzymes for digestion
d. A thick, viscous material synthesized by mucosal cells for protection against digestive juices
17. What is the function of mucus in the stomach?
a. Emulsifies fats
b. Neutralizes stomach acid
c. Digests food
d. Protects gastrointestinal cells from gastric juices
18. What substance helps suspend fat in a watery digestive mixture, making fat more available to digestive enzymes?
d. Pancreatic juices
19. Where are most digestive enzymes produced?
a. Pancreas and small intestine
b. Liver and large intestine
c. Pancreas and large intestine
d. Liver and pancreas
20. Which of the following, upon digestion, is not normally released directly into the bloodstream?
21. Which of the following body organs produces bile?
b. Salivary glands
22. Peristalsis refers to:
a. Chewing and swallowing
b. The opening and closing of sphincters
c. The action of bile on dietary fat
d. Muscular movement of materials through the GI tract
23. Where does peristalsis begin?
a. Back of the oral cavity
b. Bottom of the esophagus
c. Top of the esophagus
d. Bottom of the stomach
24. Which of the following is not considered part of the GI tract?
25. Saliva, secreted by special glands in the mouth, contains:
c. Hydrochloric acid
26. What percent of a meal has been absorbed by the time it leaves the small intestine?
27. All of the following can weaken esophageal sphincter tension and promote heartburn except:
a. Root beer
28. These protein-based substances enhance digestion by making chemical reactions more likely to happen:
29. Which of the following is true about digestive enzymes?
a. One enzyme can speed many types of chemical processes
b. Enzymes are not sensitive to temperature
c. Enzymes that work in the acidic environment of the stomach cannot work in the basic or alkaline environment of the small intestine and vice versa
d. Enzymes typically work independently of vitamins and minerals
30. Excessive acid production in the stomach or upper small intestine could result in:
a. Poor iron, calcium, and folate absorption
b. Excessive intestinal bacterial growth
c. An ulcer
d. Decreased fiber digestion and absorption
31. Absorption of nutrients by intestinal cells occurs by all the following mechanisms except:
a. Sustained absorption
b. Passive absorption
c. Active absorption
d. Facilitated absorption
32. Which pH best describes the environment of the stomach when stimulated?
b. Both acidic and basic
33. The function of thick mucus in the stomach is to:
a. Promote fat digestion
b. Activate stomach enzymes
c. Protect stomach cells from acid and enzymes
d. Keep the stomach bacteria-free
34. The hormone secretin responds to food entering the small intestine and stimulates the pancreas to release:
35. Partially digested food that enters the small intestine from the stomach is called:
36. Which of the following substances is primarily involved in the emulsification of fat to facilitate its digestion?
b. Pancreatic juices
c. Hydrochloric acid
37. Which of the following is true regarding bile?
a. It is secreted in response to the presence of carbohydrates in the small intestine
b. It stimulates the release of pancreatic juices
c. It is produced by the liver
d. It is a hormone
38. The most active area for the absorption of nutrients into the body is the:
b. Small intestine
c. Large intestine
39. The villi of the small intestine:
a. Provide an enormous surface area that facilitates absorption
b. Store fat-soluble vitamins
c. Continuously move food through the small intestine to the colon
d. Inactivate enzymes consumed with food
40. In passive absorption, nutrients enter the cell:
a. With a carrier
b. With the expenditure of energy
c. From an area of higher concentration to one of lower concentration
d. From an area of lower concentration to one of higher concentration
41. Which of the following is true of nutrient transport?
a. Fat-soluble nutrients are transported through the portal system to the liver
b. Water-soluble nutrients are transported through the portal system to the liver
c. Water-soluble nutrients are transported through the lymphatic system to the liver
d. All nutrients are transported through the lymphatic system to the liver
42. A function of the large intestine is to absorb:
a. Fats and proteins
b. Vitamins and alcohol
c. Water and minerals
d. Proteins and carbohydrates
43. Constipation can best be prevented by:
a. Eating dietary fiber
b. Appropriate fluid intake
c. Engaging in physical exercise
d. All the above
44. Which of the following is an important dietary recommendation for avoiding heartburn?
a. Eat smaller meals that are lower in fat:
b. Eat large meals
c. Eat meals low in carbohydrate
d. Restrict fluids
45. Fibers belong to the class of nutrients known as:
46. Which of the following are substances in plant foods that are not digested in the stomach or small intestine?
c. Dietary fiber
d. Simple sugars
47. Which of the following products of digestion are not normally released into the bloodstream?
48. What enzyme is responsible for carbohydrate digestion in the small intestine?
a. Salivary amylase
c. Pancreatic proteases
d. Pancreatic amylase
49. Carbohydrate digestion begins in the:
a. Stomach with gastric lipase
b. Stomach with salivary amylase
c. Mouth with salivary amylase
d. Small intestine with pancreatic amylase
50. Amylase is:
a. An enzyme that digests protein
b. Branched chain of glucose units
c. An enzyme that digests starch
d. A straight chain of glucose units
51. What is the fate of disaccharides not digested in the small intestine?
a. They pass into the colon and are absorbed
b. They pass into the colon and are fermented by bacteria
c. They are absorbed and converted to glycogen
d. They are absorbed and converted to fat
52. Which of the following shows the process of starch digestion?
a. Starch to lactose to galactose
b. Starch to maltose to glucose
c. Starch to glycogen to glucose
d. Starch to sucrose to fructose
53. Glucose is absorbed via:
a. Passive absorption
b. Facilitated absorption
c. Active absorption
d. Participatory absorption
54. Which of the following is not true of carbohydrate absorption?
a. Monosaccharides can enter the villi
b. End products of carbohydrate digestion are transported through the portal vein to the liver
c. Maltose is transported through the portal vein to the liver
d. Disaccharides are digested to monosaccharides by enzymes attached to intestinal cells
55. Lactose intolerance is caused by:
a. A milk allergy
b. Lactase deficiency
c. Milk bacteria
d. Intestinal bacteria
56. The major symptoms of lactose intolerance are:
a. Gas, abdominal pain, and distention
b. A rash, sneezing, and stuffy nose
c. A headache and chest pain
d. Nausea and vomiting
57. Which organ will receive sugars after they are absorbed into the blood?
58. When triglycerides are digested, before being absorbed, they are converted to a mixture of:
a. Diglycerides, fatty acids
b. Monoglycerides, diglycerides
c. Monoglycerides, fatty acids
d. Glycerol and fatty acids
59. After absorption, long-chain fatty acids and monoglycerides inside intestinal cells:
a. Are converted to proteins
b. Are converted to glucose
c. Are reformed into triglycerides
d. Are converted to cholesterol
60. The major fat-digesting enzyme is:
a. Salivary amylase
c. Gastric lipase
d. Pancreatic lipase
61. Which of the following is true about the fate of fatty acids after their absorption?
a. Fatty acids of 16 or more carbons enter the blood and then the liver via the portal vein
b. Fatty acids of less than 12 carbons enter the lymphatic system packaged in chylomicrons
c. Fatty acids of less than 12 carbons enter the blood and then the liver via the portal vein
d. Fatty acids of 16 or more carbons enter the lymphatic system directly
62. To be transported throughout the body, fats are packaged in structures called:
63. After chylomicrons leave the intestinal cells, they are transported via what system?
64. Lipoproteins contain the following components except:
65. What enzyme is released by the stomach to digest protein?
b. Lipoprotein lipase
66. Which of the following is not true about pepsin?
a. Amino acid chains are the digestive products of its action
b. Pepsin works best in an alkaline environment
c. Acid activates pepsin
d. Pepsin acts on food in the stomach
67. Which of the following is not true about the events during and after absorption of protein digestive breakdown products?
a. Most protein eaten ends up as individual amino acids in the blood
b. Small peptides are digested further to amino acids inside the absorptive cells of the small intestine
c. Many whole proteins are absorbed and enter the blood
d. Amino acids travel to the liver via the portal vein
68. Cooking an egg alters its appearance due to the
69. Proteins are chemically digested in which areas of the body?
a. Mouth and stomach
b. Mouth and small intestine
c. Stomach and small intestine
d. Small and large intestines