NUR 555 ADVANCED CLINICAL
PATHOPHYSIOLOGY
COMPREHENSIVE EXAM QUESTIONS
AND ANSWERS
1. Which cellular adaptation involves the replacement of one mature cell type by another,
often as a response to chronic irritation?
A. Hyperplasia
B. Atrophy
C. Dysplasia
D. Metaplasia
Answer: D
Conceptual Explanation: Metaplasia is a reversible conversion from one adult cell type to
another to better withstand chronic stress, such as the change from ciliated columnar to
squamous epithelium in smokers.
2. In the context of epigenetics, what is the primary mechanism by which DNA methylation
affects gene expression?
A. It increases the rate of transcription by attracting RNA polymerase.
,B. It silences genes by preventing the binding of transcription factors.
C. It causes silent mutations in the coding sequence.
D. It promotes histone acetylation, leading to euchromatin formation.
Answer: B
Conceptual Explanation: DNA methylation typically occurs at CpG islands and silences
gene expression by preventing transcription factor binding and recruiting proteins that
condense chromatin.
3. Which electrolyte imbalance is most commonly associated with a shortened QT interval
and muscle weakness?
A. Hypocalcemia
B. Hypermagnesemia
C. Hypercalcemia
D. Hypokalemia
Answer: C
Conceptual Explanation: Hypercalcemia shortens the plateau phase of the action
potential, leading to a shortened QT interval and decreased neuromuscular excitability.
4. A patient presents with metabolic acidosis and an elevated anion gap. Which of the
following is the most likely cause?
A. Diabetic ketoacidosis
, B. Renal tubular acidosis
C. Chronic diarrhea
D. Excessive saline administration
Answer: A
Conceptual Explanation: An elevated anion gap indicates the accumulation of
unmeasured organic acids, such as ketoacids in DKA. Diarrhea typically causes a normal
anion gap acidosis.
5. What is the pathophysiological hallmark of Type II hypersensitivity reactions?
A. Formation of antigen-antibody complexes in the circulation
B. IgE-mediated mast cell degranulation
C. T-cell mediated cytotoxicity
D. Antibodies binding to specific antigens on cell surfaces or tissues
Answer: D
Conceptual Explanation: Type II hypersensitivity is tissue-specific, where antibodies (IgG
or IgM) react with antigens on the cell membrane, leading to cell destruction or
dysfunction.
6. Which molecular change is a characteristic feature of the ‘initiation’ stage of
carcinogenesis?
A. Permanent DNA mutation following exposure to a carcinogen
PATHOPHYSIOLOGY
COMPREHENSIVE EXAM QUESTIONS
AND ANSWERS
1. Which cellular adaptation involves the replacement of one mature cell type by another,
often as a response to chronic irritation?
A. Hyperplasia
B. Atrophy
C. Dysplasia
D. Metaplasia
Answer: D
Conceptual Explanation: Metaplasia is a reversible conversion from one adult cell type to
another to better withstand chronic stress, such as the change from ciliated columnar to
squamous epithelium in smokers.
2. In the context of epigenetics, what is the primary mechanism by which DNA methylation
affects gene expression?
A. It increases the rate of transcription by attracting RNA polymerase.
,B. It silences genes by preventing the binding of transcription factors.
C. It causes silent mutations in the coding sequence.
D. It promotes histone acetylation, leading to euchromatin formation.
Answer: B
Conceptual Explanation: DNA methylation typically occurs at CpG islands and silences
gene expression by preventing transcription factor binding and recruiting proteins that
condense chromatin.
3. Which electrolyte imbalance is most commonly associated with a shortened QT interval
and muscle weakness?
A. Hypocalcemia
B. Hypermagnesemia
C. Hypercalcemia
D. Hypokalemia
Answer: C
Conceptual Explanation: Hypercalcemia shortens the plateau phase of the action
potential, leading to a shortened QT interval and decreased neuromuscular excitability.
4. A patient presents with metabolic acidosis and an elevated anion gap. Which of the
following is the most likely cause?
A. Diabetic ketoacidosis
, B. Renal tubular acidosis
C. Chronic diarrhea
D. Excessive saline administration
Answer: A
Conceptual Explanation: An elevated anion gap indicates the accumulation of
unmeasured organic acids, such as ketoacids in DKA. Diarrhea typically causes a normal
anion gap acidosis.
5. What is the pathophysiological hallmark of Type II hypersensitivity reactions?
A. Formation of antigen-antibody complexes in the circulation
B. IgE-mediated mast cell degranulation
C. T-cell mediated cytotoxicity
D. Antibodies binding to specific antigens on cell surfaces or tissues
Answer: D
Conceptual Explanation: Type II hypersensitivity is tissue-specific, where antibodies (IgG
or IgM) react with antigens on the cell membrane, leading to cell destruction or
dysfunction.
6. Which molecular change is a characteristic feature of the ‘initiation’ stage of
carcinogenesis?
A. Permanent DNA mutation following exposure to a carcinogen
