Question 1

Which of the following best describes the primary function of the enteric nervous system (ENS) in the digestive tract?

Accepted Answer

It regulates the contractile and secretory activity of the GI tract independently of the central nervous system.

Question 2

A patient is unable to absorb vitamin B12, leading to anemia. Which gastric secretion is most likely deficient in this patient?

Accepted Answer

Intrinsic factor

Question 3

Which of the following scenarios would most likely inhibit gastric emptying into the duodenum?

Accepted Answer

The presence of fatty, hypertonic, and acidic chyme in the duodenum

Question 4

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

Accepted Answer

Muscularis externa

Question 5

A patient has a blockage in the common bile duct. Which digestive process will be most directly impaired?

Accepted Answer

Emulsification and digestion of fats

Question 6

Which of the following best explains why pancreatic juice is alkaline?

Accepted Answer

It neutralizes acidic chyme entering the duodenum, providing an optimal pH for digestive enzymes.

Question 7

Which of the following is a correct sequence of events during the cephalic phase of gastric secretion?

Accepted Answer

Sight, smell, or thought of food stimulates the vagus nerve, increasing gastric juice secretion.

Question 8

Which of the following best describes the absorption of fats in the small intestine?

Accepted Answer

Fatty acids and monoglycerides are reassembled into triglycerides, packaged into chylomicrons, and enter lacteals.

Question 9

A patient with a damaged myenteric nerve plexus would most likely experience which of the following symptoms?

Accepted Answer

Impaired gastrointestinal motility

Question 10

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

Accepted Answer

They complete the final steps of digestion for carbohydrates and proteins at the surface of absorptive cells.

Question 11

Which of the following is a function of the large intestine?

Accepted Answer

Absorption of most remaining water from indigestible food residues

Question 12

If the submucosal nerve plexus is damaged, which digestive process is most likely to be affected?

Accepted Answer

Regulation of secretion and blood flow in the GI tract

Question 13

Which of the following best describes the enterohepatic circulation of bile salts?

Accepted Answer

Bile salts are secreted into the duodenum, reabsorbed in the ileum, and returned to the liver via the hepatic portal vein.

Question 14

Which of the following best explains why the stomach lining contains rugae?

Accepted Answer

To allow the stomach to expand significantly after food intake

Question 15

A patient is unable to digest lactose due to a deficiency in which enzyme?

Accepted Answer

Lactase

Question 16

Which of the following best describes the Valsalva maneuver during defecation?

Accepted Answer

It increases intra-abdominal pressure to aid in expelling feces.

Question 17

Which of the following is a correct pairing of digestive enzyme and its substrate?

Accepted Answer

Pancreatic amylase – starch

Question 18

Which of the following best explains the importance of the cardiac sphincter?

Accepted Answer

It prevents the backflow of stomach contents into the esophagus.

Question 19

Which of the following is a direct result of the enterogastric reflex?

Accepted Answer

Inhibition of gastric secretion and motility

Question 20

Which of the following best describes the fate of monosaccharides absorbed in the small intestine?

Accepted Answer

They enter the capillary blood in the villi and are transported to the liver via the hepatic portal vein.

Human Anatomy & Physiology: The Digestive System – Study Notes

Study Guide - Practice Questions