Physiology and Pathophysiology Q&A with
Rationale | Grand Canyon University
1. A patient is diagnosed with gastroesophageal reflux disease (GERD). What is the primary
pathophysiological mechanism behind this condition?
A. Excessive production of gastrin by the G cells
B. Increased esophageal peristalsis speed
C. Rapid gastric emptying into the duodenum
D. Decreased pressure in the lower esophageal sphincter (LES)
Answer: D
Rationale: GERD is primarily caused by a decrease in the resting tone of the lower
esophageal sphincter. This allow acidic gastric contents to reflux back into the esophagus,
leading to inflammation and mucosal damage. Factors like obesity, smoking, and certain
medications can contribute to this sphincter relaxation.
2. Which organism is most commonly associated with the development of chronic gastritis
and peptic ulcer disease?
A. Staphylococcus aureus
B. Escherichia coli
C. Clostridium difficile
,D. Helicobacter pylori
Answer: D
Rationale: Helicobacter pylori is a gram-negative bacterium that colonizes the gastric
mucosa. It produces urease which buffers the acidic environment, allowing the bacteria to
survive and cause chronic inflammation. This inflammation weakens the protective barrier
of the stomach, making it more susceptible to acid-induced ulcers.
3. A patient presents with epigastric pain that is relieved by eating but recurs 2 to 3 hours
after a meal. This clinical manifestation is most consistent with:
A. Duodenal ulcer
B. Gastric ulcer
C. Acute pancreatitis
D. Cholecystitis
Answer: A
Rationale: Duodenal ulcers typically present with pain that occurs when the stomach is
empty, often late at night or several hours after eating. Food acts as a buffer for the acid
entering the duodenum, which is why eating often relieves the pain. This is distinct from
gastric ulcers, where eating may actually exacerbate the pain due to stimulated acid
secretion.
, 4. Which of the following is a characteristic feature of Crohn’s disease that distinguishes it
from Ulcerative Colitis?
A. Continuous lesions limited to the mucosal layer
B. Skip lesions and transmural inflammation
C. Primarily affects the rectum and sigmoid colon
D. Absence of granulomas on biopsy
Answer: B
Rationale: Crohn’s disease can affect any part of the gastrointestinal tract and is
characterized by ‘skip lesions,’ where healthy tissue is found between inflamed segments.
The inflammation is transmural, meaning it affects all layers of the intestinal wall, which
increases the risk of fistulas. In contrast, ulcerative colitis is usually continuous and affects
only the mucosa and submucosa.
5. A patient with cirrhosis develops portal hypertension. Which complication is a direct result
of increased pressure in the portal venous system?
A. Esophageal varices
B. Asterixis
C. Hyperbilirubinemia
D. Hypoalbuminemia
Answer: A