Question 1

Which of the following best describes the primary function of the digestive system?

Accepted Answer

To break down food into nutrients that can be delivered by the bloodstream to body cells

Question 2

Which of the following organs is NOT considered an accessory organ of the digestive system?

Accepted Answer

Small intestine

Question 3

Which process is responsible for moving ingested food from one digestive organ to the next, and what is the main mechanism involved?

Accepted Answer

Propulsion; rhythmic contractions of smooth muscle (peristalsis)

Question 4

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

Accepted Answer

Muscularis externa

Question 5

A patient presents with a vitamin B12 deficiency due to impaired absorption. Which gastric cell type is most likely malfunctioning?

Accepted Answer

Parietal cells

Question 6

Which of the following best explains why the stomach can churn food into chyme?

Accepted Answer

It has an additional oblique layer of smooth muscle in the muscularis externa

Question 7

During the cephalic phase of gastric secretion, which nerve is primarily responsible for stimulating acid production in the stomach?

Accepted Answer

Vagus nerve

Question 8

Which of the following is a correct sequence of events during the swallowing (deglutition) reflex?

Accepted Answer

Tongue pushes bolus to oropharynx → soft palate elevates → epiglottis covers larynx → peristalsis moves bolus down esophagus

Question 9

Which of the following best describes the role of the enteric nervous system (ENS) in digestive motility?

Accepted Answer

It regulates short reflexes that are confined to local neurons within the digestive tract

Question 10

A patient has difficulty swallowing and food often enters the nasal cavity. Which structure is most likely not functioning properly?

Accepted Answer

Soft palate

Question 11

Which of the following is a function of saliva that directly protects against pathogens?

Accepted Answer

Lysozyme catalyzes perforation of bacterial plasma membranes

Question 12

Which of the following best explains why the esophagus is lined with stratified squamous epithelium?

Accepted Answer

To protect against abrasion from food particles

Question 13

Which hormone is released by G cells in the stomach and stimulates acid secretion?

Accepted Answer

Gastrin

Question 14

Which of the following is a correct description of the positive feedback loop involving protein digestion in the stomach?

Accepted Answer

Acid activates pepsin, which digests proteins, stimulating more gastrin release and further acid secretion

Question 15

Which of the following best explains why chyme must be released slowly into the duodenum?

Accepted Answer

To allow time for mixing with bicarbonate and water, preventing damage and osmotic imbalance

Question 16

Which of the following is a function of the greater omentum?

Accepted Answer

It supports and binds organs together and contains fat deposits

Question 17

A patient has a mutation that prevents the secretion of somatostatin in the stomach. What is the most likely consequence?

Accepted Answer

Excessive acid secretion due to lack of inhibition

Question 18

Which of the following best describes the role of the pyloric sphincter?

Accepted Answer

It regulates the flow of chyme from the stomach into the duodenum

Question 19

Which of the following best explains why the body cannot repair damaged enamel on teeth?

Accepted Answer

The cells that secrete enamel deteriorate after the tooth erupts

Question 20

Which of the following is a correct statement about the regulation of gastric motility?

Accepted Answer

Serotonin and intestinal gastrin stimulate gastric motility

Study Notes: The Digestive System (Chapter 22, Human Anatomy & Physiology)

Study Guide - Practice Questions