Question 1

Which of the following best describes the function of the alimentary canal in the digestive system?

Accepted Answer

It forms a continuous tube that digests and absorbs food, extending from the mouth to the anus.

Question 2

Which layer of the GI tract is primarily responsible for peristalsis and segmentation?

Accepted Answer

Muscularis externa

Question 3

A patient presents with pernicious anemia. Which gastric cell type is most likely malfunctioning, and what is the physiological consequence?

Accepted Answer

Parietal cells; decreased intrinsic factor production leading to impaired vitamin B$_{12}$ absorption

Question 4

During swallowing, which structure prevents food from entering the trachea?

Accepted Answer

Epiglottis

Question 5

Which of the following is a correct sequence of events during the buccal phase of swallowing?

Accepted Answer

The tongue pushes the bolus into the oropharynx, initiating voluntary swallowing.

Question 6

Which of the following best explains the role of the enteric nervous system in the GI tract?

Accepted Answer

It regulates local digestive activities independently of the central nervous system.

Question 7

Which process is responsible for moving food through the esophagus to the stomach?

Accepted Answer

Peristalsis

Question 8

A patient has a blockage in the celiac trunk. Which organs are most likely to be affected by reduced blood supply?

Accepted Answer

Spleen, liver, and stomach

Question 9

Which of the following is NOT a function of saliva?

Accepted Answer

Neutralizes stomach acid in the duodenum

Question 10

Which of the following correctly matches the digestive process with its description?

Accepted Answer

Mechanical breakdown: increases surface area of food for enzymatic digestion

Question 11

Which of the following best describes the mucosal barrier in the stomach?

Accepted Answer

A thick coating of bicarbonate-rich mucus, tight junctions between epithelial cells, and rapid cell turnover

Question 12

Which hormone is released by the stomach and stimulates gastric secretion?

Accepted Answer

Gastrin

Question 13

Which of the following is a correct statement about the muscularis externa of the stomach?

Accepted Answer

It has an additional oblique layer that aids in churning and mixing food.

Question 14

Which of the following is a function of the parietal cells in the stomach?

Accepted Answer

Secretion of hydrochloric acid and intrinsic factor

Question 15

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

Accepted Answer

Fatty chyme triggers duodenal receptors that slow gastric emptying.

Question 16

Which equation best represents the relationship between the volume of the stomach and the pressure during gastric accommodation?

Accepted Answer

$P \approx 	ext{constant}$ until $V \approx 1.5\,	ext{L}$

Question 17

Which of the following is a correct description of the enterogastric reflex?

Accepted Answer

It inhibits gastric secretion and prevents overfilling of the duodenum.

Question 18

Which of the following is a correct match between a digestive organ and its classification?

Accepted Answer

Gallbladder: accessory digestive organ

Question 19

Which of the following best describes the role of chief cells in the stomach?

Accepted Answer

They secrete pepsinogen, which is activated to pepsin by HCl.

Question 20

Which of the following is a correct description of segmentation in the digestive tract?

Accepted Answer

It is the process of mixing food and breaking it into smaller pieces by alternating contraction and relaxation of nonadjacent segments.

Digestive System Overview – Structure and Function (Marieb Human Anatomy & Physiology, Ch. 23)

Study Guide - Practice Questions