18 Oct The Digestive System

The Digestive System

 

1. The digestive system processes food, extracts nutrients, and eliminates the residue. True   False

 

2. The enteric nervous system regulates much of the digestive activity, but its action depends on the central

 

nervous system. True   False

 

3. Odor, sight, and taste stimulate salivatory nuclei in the cerebral cortex.

 

True   False

 

4. Enamel is found in the crown of a tooth, whereas dentin is part of both the crown and the root. True   False

 

5. Both chemical and mechanical digestion start in the mouth and continue in the stomach.

 

True   False

 

6. Gastric juice consists entirely of water and hydrochloric acid. True   False

 

7. Absorption of many nutrients starts in the stomach.

 

True   False

 

8. The liver is the body’s largest gland. True   False

 

9. Both pancreatic juice and bile are secreted into the duodenum.

 

True   False

 

10. The small intestine begins with the duodenum, which is its longest segment. True   False

 

11. The brush borders of intestinal absorptive cells contain numerous goblet cells.

 

True   False

 

12. Most fat is digested by pancreatic lipase. True   False

 

13. Chylomicrons are secreted from the basal surface of the absorptive cells and taken into the lacteal in the villus.

 

True   False

 

14. The large intestine absorbs water, fats, and salts. True   False

 

15. The large intestine is longer than the small intestine.

 

True   False

 

Multiple Choice Questions

 

16. The physiological process that moves a nutrient from the outside of the body to the inside is called

 

 A. ingestion

 

B. compaction

 

C. digestion

 

D. absorption

 

E. secretion

 

17. The serous membranes that suspend the stomach and intestines from the abdominal wall are called

 

A. mesenteries

 

B. mucosae

 

C. submucosae

 

D. muscularis mucosae

 

E. muscularis externa

 

18. The layer that is responsible for the motility that propels food and residue through the digestive tract is called the    .

 

A. lumen

 

B. muscularis externa

 

C. submucosa

 

D. mucosa (mucous membrane)

 

E. serosa

 

19. The outermost layer of the digestive tract, which is composed of a thin layer of areolar tissue and simple squamous epithelium, is called the                .

 

A. lumen

 

B. muscularis externa

 

C. submucosa

 

D. mucosa (mucous membrane)

 

E. serosa (mesentery)

 

20. Which of the following nutrients must be digested in order to be absorbed?

 

A. Water

 

B. Vitamins

 

C. Proteins

 

D. Minerals

 

E. Cholesterol

 

21. Which of the following is not an accessory organ of digestion?

 

A. Tongue

 

B. Liver

 

C. Pancreas

 

D. Salivary glands

 

E. Spleen

 

22. Which of the following is the accessory organ of digestion responsible for producing bile?

 

A. Tongue

 

B. Liver

 

C. Pancreas

 

D. Salivary glands

 

E. Gallbladder

 

23. Each of the following lists some of the tissue layers of the digestive tract. Which one has them incorrect order from lumen to external surface?

 

A. Lamina propria, muscularis mucosae, submucosa, muscularis externa, serosa

 

B. Serosa, lamina propria, submucosa, muscularis mucosae, muscularis externa

 

C. Mucosa, submucosa, muscularis mucosae, muscularis externa, lamina propria

 

D. Mucosa, muscularis mucosae, submucosa, muscularis externa, lamina propria

 

E. Mucosa, submucosa, muscularis externa, lamina propria, serosa

 

24. The small intestine is suspended from the abdominal wall by the       .

 

A. falciform ligament

 

B. mesentery

 

C. greater omentum

 

D. lesser omentum

 

E. esophageal hiatus

 

25. An example of chemical digestion is the break down of          into        .

 

A. proteins; nucleotides

 

B. amino acids; proteins

 

C. polysaccharides; amino acids

 

D. nucleic acids; nucleotides

 

E. fatty acids; cholesterol

 

26. The regulates digestive tract motility, secretion, and blood flow. Its neurons are found in the

 

 A. autonomic nervous system; serosa

 

B. central nervous system; muscularis externa and muscularis mucosae

 

C. enteric nervous system; submucosa and muscularis externa

 

D. visceral sensory division; muscularis externa and submucosa

 

E. visceral motor division; mucosa and submucosa

 

27. The surface of the tongue is covered with     stratified squamous epithelium, and has bumps called   , where many taste buds can be found.

 

A. keratinized; lingual papillae

 

B. keratinized; lingual frenulum

 

C. nonkeratinized; lingual papillae

 

D. nonkeratinized; tonsils

 

E. nonkeratinized; vallate papillae

 

28. Infants have                deciduous teeth, whereas adults have  permanent teeth.

 

A. 20; 32

 

B. 16; 20

 

C. 28; 20

 

D. 32; 20

 

E. 32; 32

 

29. Which of the following is the correct list of tooth anatomy from the most superficial to the deepest?

 

A. Cementum, root canal, enamel

 

B. Enamel, root canal, dentin

 

C. Dentin, enamel, cementum

 

D. Enamel, dentin, pulp

 

E. Crown, enamel, dentin

 

30. Which of the following is not normally found in saliva?

 

A. Mucus

 

B. Lysozyme

 

C. Amylase

 

D. Lipase

 

E. Protease

 

31. The gland is an extrinsic salivary gland, whereas the gland is an intrinsic salivary gland.

 

A. lingual; labial

 

B. submandibular; lingual

 

C. submandibular; sublingual

 

D. sublingual; parotid

 

E. lingual; sublingual

 

32. The swallowing center is located in the           .

 

A. mouth

 

B. oropharyn x

 

C. esophagus

 

D. medulla oblongata

 

E. enteric nervous system

 

33. The oral phase of swallowing is under             control and the pharyngo-esophageal phase is

 

 A. central nervous system; also controlled by the central nervous system

 

B. central nervous system; controlled by autonomic reflexes

 

C. autonomic nervous system; controlled by autonomic reflexes

 

D. voluntary; also voluntary

 

E. involuntary; also involuntary

 

34. Acid reflux into the esophagus (“heartburn”) is normally prevented by           .

 

A. pharyngeal constrictors

 

B. the upper esophageal sphincter

 

C. the lower esophageal sphincter (LES)

 

D. esophageal glands

 

E. pharyngeal and buccal sphincters

 

35. The regulates the flow of contents from the stomach to the duodenum.

 

A. gastric rugae

 

B. antrum

 

C. pyloric sphincter

 

D. fundus

 

E. cardial part

 

36. Hydrochloric acid (HCl) is secreted by               cells.

 

A. mucous

 

B. regenerative (stem)

 

C. parietal

 

D. chief

 

E. enteroendocrine

 

37. Necessary for Vitamin B12 absorption,            is/are secreted by           cells.

 

A. intrinsic factor; parietal

 

B. bile salts; chief

 

C. lecithin; hepatic

 

D. hydrochloric acid; parietal

 

E. enteropeptidase; mucous

 

 

 

38. Pepsinogen is produced by  and is activated by           , which is secreted by     .

 

A. chief cells; carbonic anhydrase (CAH); parietal cells

 

B. chief cells; hydrochloric acid (HCl); parietal cells

 

C. parietal cells; hydrochloric acid (HCl); chief cells

 

D. parietal cells; carbonic anhydrase (CAH); chief cells

 

E. enteroendocrine cells; carbonic anhydrase (CAH); parietal cells

 

39. Several digestive enzymes are secreted as zymogens because            .

 

A. it saves one step in their synthesis

 

B. gastric cells do not have the necessary enzymes for their synthesis

 

C. they start digesting intracellular proteins of the gastric cells more quickly

 

D. they act only in the stomach lumen and do not digest intracellular proteins

 

E. they can start digesting dietary proteins more quickly

 

40. The enterogastric reflex serves to     .

 

A. relax the stomach in preparation for swallowed food

 

B. stimulate acid and enzyme secretion when food enters the stomach

 

C. stimulate intestinal motility when there is food in the stomach

 

D. inhibit gastric motility when there is chyme in the small intestine

 

E. relax the ileocecal valve when chyme is on its way to the colon

 

41.          is a hormone, whereas  is an enzyme.

 

A. Enteropeptidase; pepsin

 

B. Gastrin; secretin

 

C. Gastrin; cholecystokinin (CCK)

 

D. Gastric lipase; histamine

 

E. Secretin; pepsin

 

42. The phase is associated with food stretching the stomach and activating myenteric and vagovagal reflexes, which in turn stimulate gastric secretions.

 

A. cephalic

 

B. gastric

 

C. intestinal

 

D. gastrointestinal

 

E. mesenteric

 

43. The stores excess glucose and releases it into the blood when needed.

 

A. pancreas

 

B. stomach

 

C. liver

 

D. spleen

 

E. small intestine

 

44. A hepatic triad consists of     .

 

A. the right, left, and common hepatic ducts

 

B. the common hepatic duct, cystic duct, and bile duct

 

C. the hepatic portal vein and two hepatic ducts

 

D. a bile ductule, a branch of the hepatic artery, and a branch of the hepatic portal vein

 

E. a central vein, a hepatic lobule, and a hepatic sinusoid

 

45.Which of the following bile components contributes to digestion?

 

A.Bile salts

 

B.Bilirubin

 

C.Bile pigments

 

D.Minerals

 

E.Cholesterol

 

46. The synthesizes bile acids by metabolizing    .

 

A. duodenum; neutral fats

 

B. ileum; bilirubin

 

C. gallbladder; cholesterol

 

D. pancreas; bile salts

 

E. liver; cholesterol

 

47. Pancreatic enzymes are secreted in response to a hormone called    .

 

A. insulin

 

B. cholecystokinin (CCK)

 

C. secretin

 

D. glucagon

 

E. gastrin

 

48. A sodium bicarbonate solution is secreted in response to a hormone called  .

 

A. insulin

 

B. cholecystokinin (CCK)

 

C. secretin

 

D. glucagon

 

E. gastrin

 

49. Which of the following is not a component of the pancreatic juice?

 

A. Trypsinogen

 

B. Chymotrypsinogen

 

C. Deoxyribonucleas e

 

D. Sodium bicarbonate

 

E. Enteropeptidase

 

50. Which of the following nutrients is absorbed by the lacteals of the small intestine?

 

A. Triglycerides

 

B. Amino acids

 

C. Glucose

 

D. Minerals

 

E. Water-soluble vitamins

 

51. Which of the following enzymes functions at the lowest pH?

 

A. Salivary amylase

 

B. Pancreatic amylase

 

C. Pepsin

 

D. Trypsin

 

E. Dipeptidase

 

52. Contact digestion takes place in/at the           .

 

A. gastric pits

 

B. surface of the gastric mucosa

 

C. intestinal crypts

 

D. brush border of the small intestine

 

E. cytoplasm in the cells of the small intestine

 

53. Which of the following is not associated with the large absorptive surface of the small intestine?

 

A. Circular folds (plicae circulares)

 

B. Intestinal length

 

C. Microvilli

 

D. Villi

 

E. Rugae

 

54. Which of the following statements regarding the migrating motor complex is true?

 

A. It milks the chyme toward the colon.

 

B. It allows a bolus to move down the esophagus.

 

C. It churns and mixes residue in the descending colon.

 

D. It churns and mixes a bolus with gastric juices.

 

E. It propels pancreatic juice down the pancreatic duct.

 

55. The of the small intestine is/are similar to the             of the stomach.

 

A. villi; pyloric glands

 

B. rugae; aggregated lymphoid nodules

 

C. intestinal crypts; gastric pits

 

D. goblet cells; parietal cells

 

E. pyloric sphincter; ileocecal valve

 

56. Carbohydrate digestion begins in the              , whereas protein digestion begins in the             .

 

A. liver; small intestine

 

B. small intestine; stomach

 

C. mouth; stomach

 

D. mouth; small intestine

 

E. stomach; small intestine

 

57. The enzyme(s) called              break(s) down the substrate called         .

 

A. lactase; glucose

 

B. peptidases; proteins

 

C. lipases; micelles

 

D. lactose; lactase

 

E. nucleases; nucleotides

 

58.Which of the following statements is true regarding the sodium-glucose transport protein (SGLT)?

 

 

 

 

 

 

 

 

 

A. It is a uniport carrier.

 

B. It is an antiport carrier.

 

C. It uses solvent drag to transport glucose and sodium.

 

D. It transports glucose and sodium from the intestinal lumen into the epithelial cells.

 

E. It transports glucose from the intestinal lumen into the epithelial cells, and sodium in the opposite direction.

 

59. Amino acids and monosaccharides are absorbed in the           , and fatty acids are absorbed in the

 

A. small intestine; large intestine

 

B. small intestine; liver

 

C. stomach; small intestine

 

D. stomach; large intestine

 

E. small intestine; small intestine

 

60. Lecithin prepares fats for hydrolysis by forming          .

 

A. triglycerides, fatty acids, and glycerol

 

B. low density lipoproteins (LDL)

 

C. chylomicrons

 

D. emulsification droplets

 

E. micelles

 

61. Which of the following is the proper sequence by which proteins are digested by different enzymes?

 

A. Pepsin, trypsin, carboxypeptidase, dipeptidase

 

B. Pepsin, trypsin, dipeptidase, carboxypeptidase

 

C. Trypsin, pepsin, carboxypeptidase, dipeptidase

 

D. Trypsin, pepsin, dipeptidase, carboxypeptidase

 

E. Dipeptidase, carboxypeptidase, pepsin, trypsin

 

62. Lipids are transported to the surface of the intestinal absorptive cells by        , and are then processed into     .

 

A. fat droplets; micelles

 

B. fat droplets; chylomicrons

 

C. micelles; fat droplets

 

D. micelles; chylomicrons

 

63. The three most abundant classes of nutrients are     .

 

A. carbohydrates, proteins, and minerals

 

B. fats, proteins, and carbohydrates

 

C. proteins, nucleic acids, and carbohydrates

 

D. triglycerides, starches, and proteins

 

E. proteins, fats, and minerals

 

64. The muscle tone of the                          along the colon contracts it lengthwise, causing its walls to bulge and form pouches called    .

 

A. circular folds; ceca

 

B. taeniae coli; haustra

 

C. haustra; taeniae coli

 

D. internal sphincters; omental (epiploic) appendages

 

E. internal sphincters; ceca

 

65. Which of the following is not a process carried out by bacterial flora?

 

A. Digestion of most of the proteins we get in the diet

 

B. Synthesis of vitamin K

 

C. Production of some of the gases found in flatus

 

D. Digestion of cellulose

 

E. Formation of part of the feces

 

66. Bacteria constitute about      % of the dry weight of the feces.

 

A. 2

 

B. 14

 

C. 30

 

D. 55

 

E. 80

 

67. Defecation is stimulated by  .

 

A. the chemical composition of the feces

 

B. bacterial flora in the feces

 

C. water content of the feces

 

D. lipid content in the feces

 

E. stretching of the rectum

 

68. Defecation is controlled by a                .

 

A. myenteric reflex only

 

B. spinal reflex only

 

C. myenteric reflex and a spinal reflex

 

69. The enzyme that catalyzes the first step reaction in HCl production by gastric parietal cells is called

 

 A. carbonic acid

 

B. carbonic anhydrase

 

C. dipeptidase

 

D. protease

 

E. ATPase

 

70. Which of the following is not a function of gastric hydrochloric acid (HCl)?

 

A. Activate pepsinogen to pepsin

 

B. Activate lingual lipase

 

C. Emulsify lipids

 

D. Destroy ingested pathogens

 

E. Convert Fe3+ to Fe2+

 

71. Which of the following is true regarding the difference between the mucosa of the small and large intestines?

 

A. They both have villi, but only the small intestine has microvilli.

 

B. The small intestine has deeper intestinal crypts than the large intestine.

 

C. The small intestine has simple columnar epithelium and the large intestine does not.

 

D. Intestinal crypts are only found in the large intestine.

 

E. The large intestine has larger circular folds than the small intestine.

 

72. Which of the following has an abundance of lymphoid tissue in the mucosa and submucosa?

 

A. small intestine

 

B. large intestine

 

C. stomach

 

D. esophagus

 

E. mouth

 

73. Which of the following is not a trigger for mass movements of the colon?

 

A. The gastrocolic reflex

 

B. The duodenocolic reflex

 

C. Chyme filling the duodenum

 

D. Chyme filling the stomach

 

E. The colorectal reflex

 

74. The movement of colonic contents from one puckered section to another is called   .

 

A. the gastrocolic reflex

 

B. the duodenocolic reflex

 

C. mass movement

 

D. haustral contraction

 

E. defecation

 

True / False Questions

 

75. All chemical digestion is essentially just hydrolysis reactions. True   False

 

76. The stomach contains enteric pacemaker cells responsible for its regular churning motion andthus

 

mechanical digestion. True   False

 

Multiple Choice Questions

 

77. Which of the following occurs in response to chemical irritants or sensory stimuli?

 

A. vomiting

 

B. mechanical digestion

 

C. segmentation

 

D. mass movement

 

True / False Questions

 

78. The small intestine uses segmentation to mix chyme with digestive enzymes, increase its contact with the mucosa, and propel it forward through the digestive tract.

 

True   False

 

79. Without a properly functioning large intestine a person will have chronic diarrhea. True   False

 

Multiple Choice Questions

 

80. Which of the following is not involved in chemical digestion?

 

A. large intestine

 

B. small intestine

 

C. stomach

 

D. mouth