Test 4 ACTUAL EXAM 2026/2027: 100%
Verified Questions & Correct Answers
Question 1: In the pathophysiology of GERD, transient lower esophageal sphincter relaxations
(TLESRs) are triggered by which mechanism involving gastric distention?
A. Vagal cholinergic stimulation only
B. Activation of gastric mechanoreceptors triggering vagal inhibitory pathways
C. Sympathetic nervous system activation
D. Direct hormonal stimulation of the LES
Correct Answer: B
Rationale: Gastric mechanoreceptors detect distention and activate vagal inhibitory pathways that
cause TLESRs, allowing reflux of gastric contents into the esophagus regardless of normal
baseline LES pressure.
Question 2: Which pathophysiological mechanism contributes to the development of Barrett's
esophagus in patients with chronic GERD?
A. Acute esophageal thermal injury
B. Chronic acid exposure inducing metaplastic transformation of esophageal epithelium
C. Direct bacterial invasion of esophageal mucosa
D. Immediate allergic reaction to gastric enzymes
Correct Answer: B
,Rationale: Chronic acid and bile exposure induces metaplastic transformation from squamous to
columnar epithelium as a protective adaptation, but this intestinal metaplasia increases cancer risk.
Question 3: In the pathophysiology of gastroparesis, delayed gastric emptying results primarily
from which neuromuscular dysfunction?
A. Excessive gastric acid production
B. Impaired gastric smooth muscle contraction and abnormal antroduodenal coordination
C. Hyperactive parasympathetic stimulation
D. Increased gastric compliance only
Correct Answer: B
Rationale: Gastroparesis involves impaired gastric smooth muscle contraction, abnormal
antroduodenal coordination, and disrupted migrating motor complex patterns, leading to delayed
gastric emptying.
Question 4: The pathophysiological hallmark of Crohn's disease involving the terminal ileum
includes which characteristic feature?
A. Superficial mucosal inflammation only
B. Transmural inflammation with skip lesions and granuloma formation
C. Limited to mucosal layer with continuous involvement
D. Vascular thrombosis as primary mechanism
Correct Answer: B
, Rationale: Crohn's disease features transmural inflammation with skip lesions (areas of normal
mucosa between diseased segments) and non-caseating granulomas, potentially affecting any
portion of the GI tract.
Question 5: In ulcerative colitis, the inflammatory process is characterized by which pattern of
mucosal involvement?
A. Transmural inflammation with skip lesions
B. Continuous superficial inflammation starting in the rectum and extending proximally
C. Patchy involvement limited to the small intestine
D. Focal granulomatous inflammation only
Correct Answer: B
Rationale: Ulcerative colitis involves continuous superficial inflammation limited to the mucosal and
submucosal layers, starting in the rectum and extending proximally without skip lesions.
Question 6: Which pathophysiological mechanism contributes to the development of toxic
megacolon in severe IBD?
A. Enhanced colonic motility
B. Colonic smooth muscle paralysis from severe inflammation and electrolyte imbalances
C. Increased parasympathetic tone
D. Mechanical obstruction only
Correct Answer: B
Rationale: Toxic megacolon results from severe colonic inflammation causing smooth muscle
paralysis, electrolyte imbalances, and loss of colonic tone, leading to massive dilation and potential
perforation.