Comprehensive Final Test (Qns & Ans)
2025
Question 1 (Multiple Choice)
Question:
Which of the following is the primary pharmacologic target of
proton pump inhibitors (PPIs) in reducing gastric acid secretion?
A) Muscarinic receptors on parietal cells
B) Histamine H₂ receptors
C) H⁺/K⁺ ATPase on the parietal cell membrane
D) Gastrin receptors
Correct ANS:
C) H⁺/K⁺ ATPase on the parietal cell membrane
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, Rationale:
PPIs irreversibly block the H⁺/K⁺ ATPase enzyme, which is the
final common pathway for acid secretion by parietal cells. This
blockade leads to a sustained reduction in gastric acid production.
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Question 2 (Fill in the Blank)
Question:
The phenomenon in which repeated exposure to acid reflux in the
distal esophagus leads to the replacement of the normal squamous
epithelium with columnar epithelium is called ________ .
Correct ANS:
Barrett's esophagus
Rationale:
Barrett's esophagus is an adaptive response to chronic
gastroesophageal reflux disease (GERD). The metaplastic change
from squamous to columnar epithelium increases the risk of
developing esophageal adenocarcinoma.
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, Question 3 (True/False)
Question:
True/False: Transmural inflammation, skip lesions, and the
potential to affect any part of the gastrointestinal tract are
characteristic pathological findings in Crohn’s disease.
Correct ANS:
True
Rationale:
Crohn’s disease is known for its patchy (skip) distribution of
inflammation, which is transmural—affecting all layers of the
bowel wall—unlike the continuous mucosal involvement seen in
ulcerative colitis.
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Question 4 (Multiple Response)
Question:
Select all factors that play a critical role in the pathogenesis of
ulcerative colitis:
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, A) Immune dysregulation
B) Genetic predisposition
C) Alterations in the gut microbiome
D) Environmental triggers
E) Transmural inflammation
Correct ANS:
A) Immune dysregulation, B) Genetic predisposition, C)
Alterations in the gut microbiome, D) Environmental triggers
Rationale:
Ulcerative colitis arises through a multifactorial process involving
dysregulated mucosal immune responses, genetic factors,
imbalances in the intestinal microbiota, and environmental
influences. Transmural inflammation (E) is not characteristic of
ulcerative colitis, which typically involves only the mucosa and
submucosa.
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Question 5 (Multiple Choice)
Question:
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