Question 1

Which of the following best describes the primary function of bile salts in the digestive process?

Accepted Answer

They emulsify fats, increasing the surface area for lipase action.

Question 2

A patient with a deficiency in intrinsic factor would most likely develop which of the following conditions?

Accepted Answer

Pernicious anemia due to impaired vitamin B12 absorption

Question 3

Which layer of the alimentary canal is responsible for peristalsis and segmentation?

Accepted Answer

Muscularis externa

Question 4

During the gastric phase of digestion, which event most strongly stimulates the release of gastrin?

Accepted Answer

Stomach distension and the presence of peptides

Question 5

Which of the following best explains why carbohydrate-rich chyme empties from the stomach faster than fat-rich chyme?

Accepted Answer

Fatty chyme triggers the release of enterogastrones that slow gastric emptying.

Question 6

Which of the following is a correct sequence of events for the activation of pancreatic proteases in the small intestine?

Accepted Answer

Trypsinogen is activated to trypsin by enteropeptidase; trypsin then activates chymotrypsinogen and procarboxypeptidase.

Question 7

A drug that blocks H2 receptors in the stomach would have which of the following effects?

Accepted Answer

Decrease the secretion of hydrochloric acid

Question 8

Which of the following best describes the role of the brush border enzymes in the small intestine?

Accepted Answer

They complete the final stages of digestion for carbohydrates and proteins.

Question 9

A patient presents with severe diarrhea after a partial colectomy. Which function of the large intestine is most likely impaired?

Accepted Answer

Absorption of water and electrolytes

Question 10

Which of the following statements about the enteric nervous system (ENS) is correct?

Accepted Answer

It regulates digestive tract motility and secretion independently of the CNS.

Question 11

Which of the following best explains why a patient with liver failure may have impaired fat digestion?

Accepted Answer

The liver produces bile salts necessary for fat emulsification.

Question 12

Which of the following is the correct pathway for the absorption of most dietary fats?

Accepted Answer

Absorbed into lacteals as chylomicrons and transported via the lymphatic system

Question 13

Which of the following best describes the process of peristalsis?

Accepted Answer

Wavelike contractions that propel food through the digestive tract

Question 14

Which of the following is a function of the Peyer's patches found in the small intestine?

Accepted Answer

Immune surveillance and protection against pathogens

Question 15

Which of the following best explains why water absorption in the small intestine is coupled with solute uptake?

Accepted Answer

Net osmosis occurs whenever a concentration gradient is established by active transport of solutes.

Question 16

A patient is taking a medication that inhibits the Na+/K+ ATPase pump in intestinal epithelial cells. Which process would be most directly affected?

Accepted Answer

Absorption of glucose and amino acids

Question 17

Which of the following is the correct chemical equation for the hydrolysis of a disaccharide (e.g., maltose) into two monosaccharides?

Accepted Answer

$$\mathrm{C$$_{12}$$H_{22}O$$_{11} + H_2O \rightarrow 2\ C_6H_{12}$$O_6$$}$

Question 18

Which of the following best describes the role of the stomach's mucosal barrier?

Accepted Answer

It protects the stomach lining from autodigestion by gastric acid and enzymes.

Question 19

Which of the following is a direct effect of cholecystokinin (CCK) release in response to fatty chyme entering the duodenum?

Accepted Answer

Contraction of the gallbladder and relaxation of the hepatopancreatic sphincter

Question 20

Which of the following best explains why a patient with a blocked common bile duct may develop steatorrhea (fatty stools)?

Accepted Answer

Bile salts cannot reach the small intestine to emulsify fats, impairing fat digestion and absorption.

The Digestive System: Structure, Function, and Regulation

Study Guide - Practice Questions