1
MSN 570 Advanced Pathophysiology Final Actual
Exam 2026/2027 | United States University | 70
Questions with Verified ,,,,answer,,,s and Rationales |
Pass Guaranteed - A+ Graded
MSN 570 Advanced Pathophysiology — 70 Exam Questions
Graduate-Level | Multiple Choice with Full Rationales
UNIT 1: CELLULAR & GENETIC PATHOPHYSIOLOGY
1. A 45-year-old woman is found to have a tumor in which cells show
uncontrolled proliferation, loss of contact inhibition, and inability to undergo
apoptosis. Which molecular mechanism MOST directly explains the failure of
apoptosis?
• A) Overexpression of the RAS proto-oncogene
• B) Inactivation of the TP53 tumor suppressor gene
• C) Amplification of HER2/neu
• D) Deletion of the retinoblastoma (RB1) gene
✅ Answer: B
Rationale: p53 (encoded by TP53) is the "guardian of the genome." It detects DNA
damage and triggers either cell cycle arrest (via p21/CDK inhibition) or apoptosis
(via BAX upregulation and BCL-2 downregulation). When TP53 is mutated or
deleted, damaged cells escape apoptosis and continue proliferating. RAS
mutations promote proliferation but not directly apoptosis evasion. HER2
amplification drives growth signaling. RB1 loss releases E2F, driving S-phase entry
— a cell cycle checkpoint issue, not apoptosis per se.
pg. 1
,2
2. A researcher notes that a cancer cell line exhibits a translocation between
chromosomes 9 and 22, producing the BCR-ABL fusion protein. What is the
PRIMARY pathophysiologic consequence?
• A) Loss of tumor suppressor activity
• B) Constitutively active tyrosine kinase signaling
• C) Epigenetic silencing of DNA repair genes
• D) Overactivation of the intrinsic apoptosis pathway
✅ Answer: B
Rationale: The Philadelphia chromosome (t[9;22]) creates the BCR-ABL fusion
oncoprotein. BCR-ABL is a constitutively active tyrosine kinase — it continuously
phosphorylates downstream proteins (RAS, PI3K/AKT, STAT5), driving relentless
proliferation and survival independent of growth factor signals. This is the
hallmark of CML and some ALL cases. Imatinib (Gleevec) was designed specifically
to inhibit this kinase. Options A, C, and D are not the primary mechanism here.
3. During cellular injury from ischemia, intracellular sodium accumulates. What is
the MOST immediate downstream consequence?
• A) Mitochondrial permeability transition pore (mPTP) opening
• B) Cellular swelling due to osmotic water influx
• C) Activation of phospholipases and membrane degradation
• D) Release of cytochrome c and apoptosis initiation
✅ Answer: B
Rationale: When the Na⁺/K⁺-ATPase fails due to ATP depletion in ischemia, Na⁺
accumulates intracellularly. Water follows osmotically, causing acute cellular
swelling (hydropic change) — the earliest and most reversible form of cell injury.
This precedes phospholipase activation (C), which occurs later with Ca²⁺ influx.
mPTP opening (A) and cytochrome c release (D) are later, irreversible events in
the apoptotic/necrotic cascade.
pg. 2
,3
4. A biopsy reveals cells with pyknotic nuclei, eosinophilic cytoplasm, and cellular
shrinkage without an inflammatory infiltrate. Which process BEST describes these
findings?
• A) Coagulative necrosis
• B) Liquefactive necrosis
• C) Apoptosis
• D) Caseous necrosis
✅ Answer: C
Rationale: Apoptosis is characterized by cell shrinkage, chromatin condensation
(pyknosis), nuclear fragmentation (karyorrhexis), membrane blebbing, and
formation of apoptotic bodies — all WITHOUT inflammation, because the process
is orderly and phosphatidylserine signals macrophages to phagocytose debris
quietly. Coagulative necrosis (A) preserves cell outlines with loss of nuclei in a
ghost-like pattern. Liquefactive necrosis (B) causes tissue dissolution (seen in
brain infarcts and abscesses). Caseous necrosis (D) has a "cheese-like" amorphous
appearance, classic for TB.
5. A 60-year-old man with chronic alcohol use has a liver biopsy showing
replacement of hepatocytes with type I collagen. Which cell type is the PRIMARY
mediator of hepatic fibrosis?
• A) Kupffer cells
• B) Hepatic stellate cells (cells of Ito)
• C) Sinusoidal endothelial cells
• D) Portal fibroblasts
✅ Answer: B
Rationale: Hepatic stellate cells (HSCs), also called Ito cells, are the master
fibrogenic cells of the liver. When activated by TGF-β1 (released from Kupffer
pg. 3
, 4
cells, injured hepatocytes, and platelets), HSCs transdifferentiate into
myofibroblasts and produce massive amounts of type I and III collagen. Kupffer
cells (A) are liver macrophages that release TGF-β and pro-inflammatory cytokines
— they initiate but do not directly produce fibrosis. Portal fibroblasts (D)
contribute but are less dominant.
UNIT 2: IMMUNOPATHOLOGY & INFLAMMATION
6. A 28-year-old woman develops acute hemolytic anemia 24 hours after
receiving a blood transfusion. The MOST likely immunological mechanism is:
• A) Type I hypersensitivity (IgE-mediated)
• B) Type II hypersensitivity (antibody-mediated cytotoxicity)
• C) Type III hypersensitivity (immune complex-mediated)
• D) Type IV hypersensitivity (delayed-type, T-cell mediated)
✅ Answer: B
Rationale: Acute hemolytic transfusion reactions result from ABO incompatibility.
Pre-formed IgM (or IgG) antibodies bind antigens on donor RBCs → complement
activation → MAC formation → intravascular hemolysis. This is the classic Type II
hypersensitivity mechanism: antibody binds cell-surface antigen →
complement/ADCC destroys the target cell. Type I (IgE) causes anaphylaxis. Type
III causes serum sickness and immune complex diseases. Type IV is contact
dermatitis, TB skin tests — no antibody involved.
7. Systemic lupus erythematosus (SLE) is characterized by loss of tolerance to self-
antigens. Which mechanism MOST contributes to the nephritis seen in SLE?
• A) Direct T-cell cytotoxicity against podocytes
• B) Deposition of anti-dsDNA/complement immune complexes in the
glomerulus
pg. 4
MSN 570 Advanced Pathophysiology Final Actual
Exam 2026/2027 | United States University | 70
Questions with Verified ,,,,answer,,,s and Rationales |
Pass Guaranteed - A+ Graded
MSN 570 Advanced Pathophysiology — 70 Exam Questions
Graduate-Level | Multiple Choice with Full Rationales
UNIT 1: CELLULAR & GENETIC PATHOPHYSIOLOGY
1. A 45-year-old woman is found to have a tumor in which cells show
uncontrolled proliferation, loss of contact inhibition, and inability to undergo
apoptosis. Which molecular mechanism MOST directly explains the failure of
apoptosis?
• A) Overexpression of the RAS proto-oncogene
• B) Inactivation of the TP53 tumor suppressor gene
• C) Amplification of HER2/neu
• D) Deletion of the retinoblastoma (RB1) gene
✅ Answer: B
Rationale: p53 (encoded by TP53) is the "guardian of the genome." It detects DNA
damage and triggers either cell cycle arrest (via p21/CDK inhibition) or apoptosis
(via BAX upregulation and BCL-2 downregulation). When TP53 is mutated or
deleted, damaged cells escape apoptosis and continue proliferating. RAS
mutations promote proliferation but not directly apoptosis evasion. HER2
amplification drives growth signaling. RB1 loss releases E2F, driving S-phase entry
— a cell cycle checkpoint issue, not apoptosis per se.
pg. 1
,2
2. A researcher notes that a cancer cell line exhibits a translocation between
chromosomes 9 and 22, producing the BCR-ABL fusion protein. What is the
PRIMARY pathophysiologic consequence?
• A) Loss of tumor suppressor activity
• B) Constitutively active tyrosine kinase signaling
• C) Epigenetic silencing of DNA repair genes
• D) Overactivation of the intrinsic apoptosis pathway
✅ Answer: B
Rationale: The Philadelphia chromosome (t[9;22]) creates the BCR-ABL fusion
oncoprotein. BCR-ABL is a constitutively active tyrosine kinase — it continuously
phosphorylates downstream proteins (RAS, PI3K/AKT, STAT5), driving relentless
proliferation and survival independent of growth factor signals. This is the
hallmark of CML and some ALL cases. Imatinib (Gleevec) was designed specifically
to inhibit this kinase. Options A, C, and D are not the primary mechanism here.
3. During cellular injury from ischemia, intracellular sodium accumulates. What is
the MOST immediate downstream consequence?
• A) Mitochondrial permeability transition pore (mPTP) opening
• B) Cellular swelling due to osmotic water influx
• C) Activation of phospholipases and membrane degradation
• D) Release of cytochrome c and apoptosis initiation
✅ Answer: B
Rationale: When the Na⁺/K⁺-ATPase fails due to ATP depletion in ischemia, Na⁺
accumulates intracellularly. Water follows osmotically, causing acute cellular
swelling (hydropic change) — the earliest and most reversible form of cell injury.
This precedes phospholipase activation (C), which occurs later with Ca²⁺ influx.
mPTP opening (A) and cytochrome c release (D) are later, irreversible events in
the apoptotic/necrotic cascade.
pg. 2
,3
4. A biopsy reveals cells with pyknotic nuclei, eosinophilic cytoplasm, and cellular
shrinkage without an inflammatory infiltrate. Which process BEST describes these
findings?
• A) Coagulative necrosis
• B) Liquefactive necrosis
• C) Apoptosis
• D) Caseous necrosis
✅ Answer: C
Rationale: Apoptosis is characterized by cell shrinkage, chromatin condensation
(pyknosis), nuclear fragmentation (karyorrhexis), membrane blebbing, and
formation of apoptotic bodies — all WITHOUT inflammation, because the process
is orderly and phosphatidylserine signals macrophages to phagocytose debris
quietly. Coagulative necrosis (A) preserves cell outlines with loss of nuclei in a
ghost-like pattern. Liquefactive necrosis (B) causes tissue dissolution (seen in
brain infarcts and abscesses). Caseous necrosis (D) has a "cheese-like" amorphous
appearance, classic for TB.
5. A 60-year-old man with chronic alcohol use has a liver biopsy showing
replacement of hepatocytes with type I collagen. Which cell type is the PRIMARY
mediator of hepatic fibrosis?
• A) Kupffer cells
• B) Hepatic stellate cells (cells of Ito)
• C) Sinusoidal endothelial cells
• D) Portal fibroblasts
✅ Answer: B
Rationale: Hepatic stellate cells (HSCs), also called Ito cells, are the master
fibrogenic cells of the liver. When activated by TGF-β1 (released from Kupffer
pg. 3
, 4
cells, injured hepatocytes, and platelets), HSCs transdifferentiate into
myofibroblasts and produce massive amounts of type I and III collagen. Kupffer
cells (A) are liver macrophages that release TGF-β and pro-inflammatory cytokines
— they initiate but do not directly produce fibrosis. Portal fibroblasts (D)
contribute but are less dominant.
UNIT 2: IMMUNOPATHOLOGY & INFLAMMATION
6. A 28-year-old woman develops acute hemolytic anemia 24 hours after
receiving a blood transfusion. The MOST likely immunological mechanism is:
• A) Type I hypersensitivity (IgE-mediated)
• B) Type II hypersensitivity (antibody-mediated cytotoxicity)
• C) Type III hypersensitivity (immune complex-mediated)
• D) Type IV hypersensitivity (delayed-type, T-cell mediated)
✅ Answer: B
Rationale: Acute hemolytic transfusion reactions result from ABO incompatibility.
Pre-formed IgM (or IgG) antibodies bind antigens on donor RBCs → complement
activation → MAC formation → intravascular hemolysis. This is the classic Type II
hypersensitivity mechanism: antibody binds cell-surface antigen →
complement/ADCC destroys the target cell. Type I (IgE) causes anaphylaxis. Type
III causes serum sickness and immune complex diseases. Type IV is contact
dermatitis, TB skin tests — no antibody involved.
7. Systemic lupus erythematosus (SLE) is characterized by loss of tolerance to self-
antigens. Which mechanism MOST contributes to the nephritis seen in SLE?
• A) Direct T-cell cytotoxicity against podocytes
• B) Deposition of anti-dsDNA/complement immune complexes in the
glomerulus
pg. 4
