NR507-NP ACTUAL EXAM
2026/2027 | Version 1 | Advanced
Pathophysiology | Verified Q&A |
Pass Guaranteed - A+ Graded
DOMAIN 1: CELLULAR INJURY, ADAPTATION, AND
NEOPLASIA
Questions 1-15
Q1: A 68-year-old male with a 40-pack-year smoking history presents with progressive
dyspnea and a chronic productive cough. Lung biopsy reveals bronchial epithelium with areas
of stratified squamous epithelium replacing the normal pseudostratified ciliated columnar
epithelium. Which cellular adaptation BEST explains this histologic finding?
A. Hypertrophy—an increase in cell size to meet increased metabolic demands [INCORRECT]
B. Hyperplasia—an increase in cell number in response to chronic irritation [INCORRECT]
C. Metaplasia—reversible substitution of one differentiated cell type for another [CORRECT]
D. Dysplasia—disordered, defective cell growth representing pre-malignant change
[INCORRECT]
Correct Answer: C
Rationale: Metaplasia is the reversible replacement of one differentiated cell type by another,
typically in response to chronic irritation. In this case, chronic smoking irritation has caused
bronchial epithelium to undergo squamous metaplasia (Barrett esophagus is another classic
example). This adaptation is reversible if the irritant is removed but predisposes to dysplasia
and subsequent carcinoma. Distractor Analysis: (A) Hypertrophy involves increased cell size,
not type change; (B) Hyperplasia increases cell number but maintains the same cell type; (D)
Dysplasia involves disordered growth with nuclear atypia—while this patient is at risk, the
described change is metaplasia, not yet dysplasia.
,Q2: A 55-year-old female receiving cyclophosphamide and doxorubicin for breast cancer
develops acute myeloid leukemia 4 years after completing chemotherapy. Molecular analysis
reveals TP53 mutations in the leukemic cells. Which pathophysiologic mechanism BEST
explains this secondary malignancy?
A. Activation of proto-oncogenes leading to sustained proliferative signaling [INCORRECT]
B. Direct DNA cross-linking by alkylating agents causing TP53 mutations and genomic
instability [CORRECT]
C. HER2 receptor overexpression promoting uncontrolled cellular proliferation [INCORRECT]
D. Epigenetic silencing of tumor suppressor genes without DNA sequence alteration
[INCORRECT]
Correct Answer: B
Rationale: Alkylating agents (cyclophosphamide) create DNA cross-links that directly
damage DNA. If repair mechanisms fail, mutations accumulate in critical genes like TP53
(the "guardian of the genome"), leading to genomic instability—a hallmark of cancer. This
explains the 4-10 year latency period for therapy-related myeloid neoplasms. Distractor
Analysis: (A) describes oncogene activation but not chemotherapy-induced secondary
malignancy; (C) describes trastuzumab-responsive breast cancer mechanism, not alkylating
agent toxicity; (D) describes epigenetic changes, not the direct DNA damage characteristic of
alkylating agents.
Q3: A patient with multiple myeloma is receiving trastuzumab therapy. Which specific
oncogenic pathway is being targeted by this monoclonal antibody?
A. Epidermal growth factor receptor (EGFR) signaling pathway [INCORRECT]
B. Vascular endothelial growth factor (VEGF) angiogenesis pathway [INCORRECT]
C. Human epidermal growth factor receptor 2 (HER2) sustained proliferative signaling
[CORRECT]
D. Programmed cell death protein 1 (PD-1) immune checkpoint pathway [INCORRECT]
Correct Answer: C
Rationale: Trastuzumab is a humanized monoclonal antibody that binds the extracellular
domain of HER2 (ERBB2), a receptor tyrosine kinase that promotes sustained proliferative
signaling when overexpressed. By blocking HER2, trastuzumab inhibits downstream PI3K/Akt
,and MAPK pathways, inducing apoptosis and preventing cellular proliferation. Distractor
Analysis: (A) is targeted by cetuximab/erlotinib; (B) by bevacizumab; (D) by
pembrolizumab/nivolumab.
Q4: A liver biopsy from a patient with acute viral hepatitis shows hepatocytes with swollen,
clear cytoplasm and displaced nuclei. Which type of cellular injury is present?
A. Coagulative necrosis—preservation of cellular architecture with loss of nuclei
[INCORRECT]
B. Liquefactive necrosis—enzymatic digestion forming soft, liquid debris [INCORRECT]
C. Hydropic change—reversible ATP depletion causing Na+/K+ pump failure and water influx
[CORRECT]
D. Caseous necrosis—amorphous, eosinophilic debris with granulomatous inflammation
[INCORRECT]
Correct Answer: C
Rationale: Hydropic (vacuolar) degeneration is reversible cellular injury characterized by
cellular swelling due to ATP depletion. Failure of the Na+/K+-ATPase pump leads to
intracellular sodium accumulation, water influx via osmosis, and dilation of the endoplasmic
reticulum. This is seen in early viral hepatitis, hypoxic injury, and toxic insults. Distractor
Analysis: (A) is seen in myocardial infarction; (B) in cerebral infarction or abscesses; (D) in
tuberculosis.
Q5: A 45-year-old female with BRCA1 mutation status presents with ductal carcinoma in situ
(DCIS) of the breast. Pathology reveals loss of heterozygosity at the RB locus. Which
hallmark of cancer is MOST directly facilitated by this genetic alteration?
A. Evasion of growth suppressors through loss of cell cycle checkpoint control [CORRECT]
B. Sustained angiogenesis via VEGF overexpression [INCORRECT]
C. Tissue invasion and metastasis through basement membrane degradation [INCORRECT]
D. Replicative immortality through telomerase activation [INCORRECT]
Correct Answer: A
Rationale: The retinoblastoma (RB) tumor suppressor protein regulates the G1/S cell cycle
checkpoint by binding E2F transcription factors. Loss of RB function (through mutation,
, deletion, or inactivation by viral oncoproteins) removes critical growth suppression, allowing
uncontrolled cellular proliferation. This represents evasion of growth suppressors—one of
the hallmarks of cancer. Distractor Analysis: (B) involves HIF-1α/VEGF pathways; (C) involves
MMPs and EMT; (D) involves hTERT activation.
Q6: A patient with chronic lymphocytic leukemia demonstrates resistance to chemotherapy.
Flow cytometry reveals overexpression of Bcl-2 protein. Which pathophysiologic mechanism
explains this treatment resistance?
A. Defective DNA mismatch repair leading to microsatellite instability [INCORRECT]
B. Inhibition of pro-apoptotic proteins allowing evasion of programmed cell death [CORRECT]
C. Enhanced nucleotide excision repair preventing platinum-DNA adduct formation
[INCORRECT]
D. Upregulation of multidrug resistance pumps increasing drug efflux [INCORRECT]
Correct Answer: B
Rationale: Bcl-2 is an anti-apoptotic protein that localizes to the outer mitochondrial
membrane, preventing cytochrome c release and caspase activation. Overexpression (often
due to t(14;18) translocation in follicular lymphoma) blocks the intrinsic apoptotic pathway,
allowing malignant cells to survive despite chemotherapy-induced DNA damage. Distractor
Analysis: (A) describes Lynch syndrome mechanism; (C) describes cisplatin resistance; (D)
describes P-glycoprotein-mediated resistance.
Q7: A bone marrow biopsy from a patient with multiple myeloma shows extensive plasma
cell infiltration. These cells demonstrate activation of the unfolded protein response (UPR).
Which cellular process necessitates this adaptive response?
A. Rapid cellular division requiring increased DNA replication [INCORRECT]
B. Massive immunoglobulin synthesis exceeding endoplasmic reticulum folding capacity
[CORRECT]
C. Aerobic glycolysis (Warburg effect) generating excessive lactate [INCORRECT]
D. Lysosomal accumulation of undigested cellular debris [INCORRECT]
Correct Answer: B
2026/2027 | Version 1 | Advanced
Pathophysiology | Verified Q&A |
Pass Guaranteed - A+ Graded
DOMAIN 1: CELLULAR INJURY, ADAPTATION, AND
NEOPLASIA
Questions 1-15
Q1: A 68-year-old male with a 40-pack-year smoking history presents with progressive
dyspnea and a chronic productive cough. Lung biopsy reveals bronchial epithelium with areas
of stratified squamous epithelium replacing the normal pseudostratified ciliated columnar
epithelium. Which cellular adaptation BEST explains this histologic finding?
A. Hypertrophy—an increase in cell size to meet increased metabolic demands [INCORRECT]
B. Hyperplasia—an increase in cell number in response to chronic irritation [INCORRECT]
C. Metaplasia—reversible substitution of one differentiated cell type for another [CORRECT]
D. Dysplasia—disordered, defective cell growth representing pre-malignant change
[INCORRECT]
Correct Answer: C
Rationale: Metaplasia is the reversible replacement of one differentiated cell type by another,
typically in response to chronic irritation. In this case, chronic smoking irritation has caused
bronchial epithelium to undergo squamous metaplasia (Barrett esophagus is another classic
example). This adaptation is reversible if the irritant is removed but predisposes to dysplasia
and subsequent carcinoma. Distractor Analysis: (A) Hypertrophy involves increased cell size,
not type change; (B) Hyperplasia increases cell number but maintains the same cell type; (D)
Dysplasia involves disordered growth with nuclear atypia—while this patient is at risk, the
described change is metaplasia, not yet dysplasia.
,Q2: A 55-year-old female receiving cyclophosphamide and doxorubicin for breast cancer
develops acute myeloid leukemia 4 years after completing chemotherapy. Molecular analysis
reveals TP53 mutations in the leukemic cells. Which pathophysiologic mechanism BEST
explains this secondary malignancy?
A. Activation of proto-oncogenes leading to sustained proliferative signaling [INCORRECT]
B. Direct DNA cross-linking by alkylating agents causing TP53 mutations and genomic
instability [CORRECT]
C. HER2 receptor overexpression promoting uncontrolled cellular proliferation [INCORRECT]
D. Epigenetic silencing of tumor suppressor genes without DNA sequence alteration
[INCORRECT]
Correct Answer: B
Rationale: Alkylating agents (cyclophosphamide) create DNA cross-links that directly
damage DNA. If repair mechanisms fail, mutations accumulate in critical genes like TP53
(the "guardian of the genome"), leading to genomic instability—a hallmark of cancer. This
explains the 4-10 year latency period for therapy-related myeloid neoplasms. Distractor
Analysis: (A) describes oncogene activation but not chemotherapy-induced secondary
malignancy; (C) describes trastuzumab-responsive breast cancer mechanism, not alkylating
agent toxicity; (D) describes epigenetic changes, not the direct DNA damage characteristic of
alkylating agents.
Q3: A patient with multiple myeloma is receiving trastuzumab therapy. Which specific
oncogenic pathway is being targeted by this monoclonal antibody?
A. Epidermal growth factor receptor (EGFR) signaling pathway [INCORRECT]
B. Vascular endothelial growth factor (VEGF) angiogenesis pathway [INCORRECT]
C. Human epidermal growth factor receptor 2 (HER2) sustained proliferative signaling
[CORRECT]
D. Programmed cell death protein 1 (PD-1) immune checkpoint pathway [INCORRECT]
Correct Answer: C
Rationale: Trastuzumab is a humanized monoclonal antibody that binds the extracellular
domain of HER2 (ERBB2), a receptor tyrosine kinase that promotes sustained proliferative
signaling when overexpressed. By blocking HER2, trastuzumab inhibits downstream PI3K/Akt
,and MAPK pathways, inducing apoptosis and preventing cellular proliferation. Distractor
Analysis: (A) is targeted by cetuximab/erlotinib; (B) by bevacizumab; (D) by
pembrolizumab/nivolumab.
Q4: A liver biopsy from a patient with acute viral hepatitis shows hepatocytes with swollen,
clear cytoplasm and displaced nuclei. Which type of cellular injury is present?
A. Coagulative necrosis—preservation of cellular architecture with loss of nuclei
[INCORRECT]
B. Liquefactive necrosis—enzymatic digestion forming soft, liquid debris [INCORRECT]
C. Hydropic change—reversible ATP depletion causing Na+/K+ pump failure and water influx
[CORRECT]
D. Caseous necrosis—amorphous, eosinophilic debris with granulomatous inflammation
[INCORRECT]
Correct Answer: C
Rationale: Hydropic (vacuolar) degeneration is reversible cellular injury characterized by
cellular swelling due to ATP depletion. Failure of the Na+/K+-ATPase pump leads to
intracellular sodium accumulation, water influx via osmosis, and dilation of the endoplasmic
reticulum. This is seen in early viral hepatitis, hypoxic injury, and toxic insults. Distractor
Analysis: (A) is seen in myocardial infarction; (B) in cerebral infarction or abscesses; (D) in
tuberculosis.
Q5: A 45-year-old female with BRCA1 mutation status presents with ductal carcinoma in situ
(DCIS) of the breast. Pathology reveals loss of heterozygosity at the RB locus. Which
hallmark of cancer is MOST directly facilitated by this genetic alteration?
A. Evasion of growth suppressors through loss of cell cycle checkpoint control [CORRECT]
B. Sustained angiogenesis via VEGF overexpression [INCORRECT]
C. Tissue invasion and metastasis through basement membrane degradation [INCORRECT]
D. Replicative immortality through telomerase activation [INCORRECT]
Correct Answer: A
Rationale: The retinoblastoma (RB) tumor suppressor protein regulates the G1/S cell cycle
checkpoint by binding E2F transcription factors. Loss of RB function (through mutation,
, deletion, or inactivation by viral oncoproteins) removes critical growth suppression, allowing
uncontrolled cellular proliferation. This represents evasion of growth suppressors—one of
the hallmarks of cancer. Distractor Analysis: (B) involves HIF-1α/VEGF pathways; (C) involves
MMPs and EMT; (D) involves hTERT activation.
Q6: A patient with chronic lymphocytic leukemia demonstrates resistance to chemotherapy.
Flow cytometry reveals overexpression of Bcl-2 protein. Which pathophysiologic mechanism
explains this treatment resistance?
A. Defective DNA mismatch repair leading to microsatellite instability [INCORRECT]
B. Inhibition of pro-apoptotic proteins allowing evasion of programmed cell death [CORRECT]
C. Enhanced nucleotide excision repair preventing platinum-DNA adduct formation
[INCORRECT]
D. Upregulation of multidrug resistance pumps increasing drug efflux [INCORRECT]
Correct Answer: B
Rationale: Bcl-2 is an anti-apoptotic protein that localizes to the outer mitochondrial
membrane, preventing cytochrome c release and caspase activation. Overexpression (often
due to t(14;18) translocation in follicular lymphoma) blocks the intrinsic apoptotic pathway,
allowing malignant cells to survive despite chemotherapy-induced DNA damage. Distractor
Analysis: (A) describes Lynch syndrome mechanism; (C) describes cisplatin resistance; (D)
describes P-glycoprotein-mediated resistance.
Q7: A bone marrow biopsy from a patient with multiple myeloma shows extensive plasma
cell infiltration. These cells demonstrate activation of the unfolded protein response (UPR).
Which cellular process necessitates this adaptive response?
A. Rapid cellular division requiring increased DNA replication [INCORRECT]
B. Massive immunoglobulin synthesis exceeding endoplasmic reticulum folding capacity
[CORRECT]
C. Aerobic glycolysis (Warburg effect) generating excessive lactate [INCORRECT]
D. Lysosomal accumulation of undigested cellular debris [INCORRECT]
Correct Answer: B
