, Question 1
Which molecular event most directly initiates the intrinsic pathway of
apoptosis following irreparable DNA damage?
A. Release of cytochrome c from mitochondria and formation of the
apoptosome.
B. Activation of caspase-8 by death receptors.
C. Increased permeability of the outer mitochondrial membrane due to
Bcl-2 overexpression.
D. Direct activation of caspase-3 by p53.
Correct Answer: A - Release of cytochrome c from mitochondria
and formation of the apoptosome.
RATIONALE
The intrinsic pathway is triggered by mitochondrial outer membrane
permeabilization, releasing cytochrome c, which binds Apaf-1 to form
the apoptosome and activate caspase-9. B describes the extrinsic
pathway; C is incorrect because Bcl-2 is anti-apoptotic; D is wrong as
p53 induces Bax/Bak but does not directly activate caspase-3.
Question 2
In a patient with septic shock, which combination of hemodynamic parameters
best distinguishes it from cardiogenic shock?
A. Low central venous pressure (CVP), low cardiac output (CO), high
systemic vascular resistance (SVR).
B. High CVP, high CO, low SVR.
C. Low CVP, high CO, low SVR.
D. High CVP, low CO, high SVR.
Correct Answer: C - Low CVP, high CO, low SVR.
Page 2
, RATIONALE
Septic shock is characterized by vasodilation (low SVR), which leads
to low CVP and compensatory high CO. Cardiogenic shock typically
shows high CVP, low CO, and high SVR due to pump failure and
compensatory vasoconstriction.
Question 3
Which statement accurately describes the role of tumor necrosis factor-alpha
(TNF-) in rheumatoid arthritis pathogenesis?
A. It primarily inhibits osteoclast activity, reducing bone erosion.
B. It promotes synovial fibroblast proliferation and matrix
metalloproteinase production, leading to joint destruction.
C. It downregulates adhesion molecules, decreasing leukocyte migration
into synovium.
D. It induces regulatory T-cell differentiation, suppressing inflammation.
Correct Answer: B - It promotes synovial fibroblast proliferation
and matrix metalloproteinase production, leading to joint
destruction.
RATIONALE
TNF- drives synovial inflammation by activating fibroblasts,
increasing MMPs, and promoting osteoclastogenesis, leading to
cartilage and bone destruction. The other options describe
anti-inflammatory or protective effects not typical of TNF- in RA.
Question 4
A patient with type 2 diabetes has a fasting glucose of 180 mg/dL and HbA1c
of 8.5%. Which pathophysiological mechanism is most responsible for
increased hepatic glucose output?
A. Increased insulin sensitivity in the liver.
B. Excessive glucagon secretion and hepatic insulin resistance.
Page 3
, C. Enhanced peripheral glucose uptake.
D. Decreased gluconeogenic enzyme activity.
Correct Answer: B - Excessive glucagon secretion and hepatic
insulin resistance.
RATIONALE
In type 2 diabetes, hepatic insulin resistance and hyperglucagonemia
stimulate glycogenolysis and gluconeogenesis, increasing hepatic
glucose output. The other options would lower glucose, not raise it.
Question 5
Which acid-base disorder is most likely in a patient with prolonged vomiting
and a nasogastric tube to suction?
A. Metabolic acidosis with increased anion gap.
B. Metabolic alkalosis with hypokalemia.
C. Respiratory acidosis with hypoxemia.
D. Respiratory alkalosis with hyperkalemia.
Correct Answer: B - Metabolic alkalosis with hypokalemia.
RATIONALE
Loss of gastric HCl leads to metabolic alkalosis; volume depletion
causes secondary hyperaldosteronism, promoting renal K+ excretion
and hypokalemia. The other options do not match the expected
physiology.
Question 6
In acute respiratory distress syndrome (ARDS), which ventilator strategy is
most consistent with current evidence to reduce mortality?
A. High tidal volumes (12 mL/kg) to improve oxygenation.
B. Low tidal volumes (6 mL/kg predicted body weight) and plateau
pressure 30 cm H2O.
C. High positive end-expiratory pressure (PEEP) without limiting tidal
Page 4
Which molecular event most directly initiates the intrinsic pathway of
apoptosis following irreparable DNA damage?
A. Release of cytochrome c from mitochondria and formation of the
apoptosome.
B. Activation of caspase-8 by death receptors.
C. Increased permeability of the outer mitochondrial membrane due to
Bcl-2 overexpression.
D. Direct activation of caspase-3 by p53.
Correct Answer: A - Release of cytochrome c from mitochondria
and formation of the apoptosome.
RATIONALE
The intrinsic pathway is triggered by mitochondrial outer membrane
permeabilization, releasing cytochrome c, which binds Apaf-1 to form
the apoptosome and activate caspase-9. B describes the extrinsic
pathway; C is incorrect because Bcl-2 is anti-apoptotic; D is wrong as
p53 induces Bax/Bak but does not directly activate caspase-3.
Question 2
In a patient with septic shock, which combination of hemodynamic parameters
best distinguishes it from cardiogenic shock?
A. Low central venous pressure (CVP), low cardiac output (CO), high
systemic vascular resistance (SVR).
B. High CVP, high CO, low SVR.
C. Low CVP, high CO, low SVR.
D. High CVP, low CO, high SVR.
Correct Answer: C - Low CVP, high CO, low SVR.
Page 2
, RATIONALE
Septic shock is characterized by vasodilation (low SVR), which leads
to low CVP and compensatory high CO. Cardiogenic shock typically
shows high CVP, low CO, and high SVR due to pump failure and
compensatory vasoconstriction.
Question 3
Which statement accurately describes the role of tumor necrosis factor-alpha
(TNF-) in rheumatoid arthritis pathogenesis?
A. It primarily inhibits osteoclast activity, reducing bone erosion.
B. It promotes synovial fibroblast proliferation and matrix
metalloproteinase production, leading to joint destruction.
C. It downregulates adhesion molecules, decreasing leukocyte migration
into synovium.
D. It induces regulatory T-cell differentiation, suppressing inflammation.
Correct Answer: B - It promotes synovial fibroblast proliferation
and matrix metalloproteinase production, leading to joint
destruction.
RATIONALE
TNF- drives synovial inflammation by activating fibroblasts,
increasing MMPs, and promoting osteoclastogenesis, leading to
cartilage and bone destruction. The other options describe
anti-inflammatory or protective effects not typical of TNF- in RA.
Question 4
A patient with type 2 diabetes has a fasting glucose of 180 mg/dL and HbA1c
of 8.5%. Which pathophysiological mechanism is most responsible for
increased hepatic glucose output?
A. Increased insulin sensitivity in the liver.
B. Excessive glucagon secretion and hepatic insulin resistance.
Page 3
, C. Enhanced peripheral glucose uptake.
D. Decreased gluconeogenic enzyme activity.
Correct Answer: B - Excessive glucagon secretion and hepatic
insulin resistance.
RATIONALE
In type 2 diabetes, hepatic insulin resistance and hyperglucagonemia
stimulate glycogenolysis and gluconeogenesis, increasing hepatic
glucose output. The other options would lower glucose, not raise it.
Question 5
Which acid-base disorder is most likely in a patient with prolonged vomiting
and a nasogastric tube to suction?
A. Metabolic acidosis with increased anion gap.
B. Metabolic alkalosis with hypokalemia.
C. Respiratory acidosis with hypoxemia.
D. Respiratory alkalosis with hyperkalemia.
Correct Answer: B - Metabolic alkalosis with hypokalemia.
RATIONALE
Loss of gastric HCl leads to metabolic alkalosis; volume depletion
causes secondary hyperaldosteronism, promoting renal K+ excretion
and hypokalemia. The other options do not match the expected
physiology.
Question 6
In acute respiratory distress syndrome (ARDS), which ventilator strategy is
most consistent with current evidence to reduce mortality?
A. High tidal volumes (12 mL/kg) to improve oxygenation.
B. Low tidal volumes (6 mL/kg predicted body weight) and plateau
pressure 30 cm H2O.
C. High positive end-expiratory pressure (PEEP) without limiting tidal
Page 4
