COMSAE® PHASE 1 FORM 110:
COMPREHENSIVE PRACTICE EXAMINATION
FOR COMLEX-USA LEVEL 1 READINESS
QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES || 100%
GUARANTEED PASS!!
<LATEST VERSION>
Question 1
A 24-year-old medical student develops neck stiffness and headache after studying
for several hours. Examination reveals restricted rotation at C2 with increased
tissue texture changes on the right. Which muscle is most likely contributing to this
dysfunction?
A. Longus colli
B. Splenius capitis
C. Sternocleidomastoid
D. Scalenus anterior
E. Levator scapulae
Correct Answer: B
Rationale:
The splenius capitis extends, rotates, and sidebends the head ipsilaterally.
Hypertonicity can restrict cervical rotation and contribute to headache patterns
commonly seen with upper cervical dysfunction.
,Question 2
A patient presents with confusion, ataxia, and ophthalmoplegia. Chronic alcohol
use is noted. Which biochemical process is most directly impaired?
A. DNA synthesis
B. Oxidative phosphorylation
C. Pyruvate dehydrogenase activity
D. Fatty acid β-oxidation
E. Heme synthesis
Correct Answer: C
Rationale:
Thiamine deficiency impairs pyruvate dehydrogenase, preventing conversion of
pyruvate to acetyl-CoA, leading to neurologic deficits seen in Wernicke
encephalopathy.
Question 3
A gram-positive, catalase-positive organism grows in clusters and produces
coagulase. Which virulence factor allows immune evasion?
A. Protein A
B. Lipoteichoic acid
C. Streptolysin O
D. IgA protease
E. M protein
Correct Answer: A
Rationale:
Protein A binds the Fc portion of IgG, preventing opsonization and phagocytosis, a
hallmark of Staphylococcus aureus.
,Question 4
A patient has hyperplasia of the zona fasciculata. Which hormone level is most
likely elevated?
A. Aldosterone
B. Cortisol
C. Androstenedione
D. Epinephrine
E. Renin
Correct Answer: B
Rationale:
The zona fasciculata produces cortisol. Hyperplasia leads to excess cortisol,
producing Cushingoid features.
Question 5
A newborn fails to pass meconium and develops abdominal distension. Biopsy
shows absence of ganglion cells in the colon. What embryologic structure failed to
migrate?
A. Neural tube
B. Mesoderm
C. Neural crest cells
D. Endoderm
E. Notochord
Correct Answer: C
Rationale:
Hirschsprung disease results from failure of neural crest cell migration into the
colon, causing aganglionic megacolon.
, Question 6
A patient with atrial fibrillation is started on a medication that prolongs phase 3 of
the cardiac action potential. Which ion channel is affected?
A. Sodium
B. Calcium
C. Potassium
D. Chloride
E. Magnesium
Correct Answer: C
Rationale:
Phase 3 repolarization is mediated by potassium efflux. Potassium channel
blockade prolongs repolarization and refractory period.
Question 7
Which viscerosomatic reflex level is most associated with gastric pathology?
A. T1–T4
B. T5–T9
C. T10–T12
D. L1–L2
E. S2–S4
Correct Answer: B
Rationale:
The stomach receives sympathetic innervation from T5–T9, commonly producing
viscerosomatic findings at these levels.
COMPREHENSIVE PRACTICE EXAMINATION
FOR COMLEX-USA LEVEL 1 READINESS
QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES || 100%
GUARANTEED PASS!!
<LATEST VERSION>
Question 1
A 24-year-old medical student develops neck stiffness and headache after studying
for several hours. Examination reveals restricted rotation at C2 with increased
tissue texture changes on the right. Which muscle is most likely contributing to this
dysfunction?
A. Longus colli
B. Splenius capitis
C. Sternocleidomastoid
D. Scalenus anterior
E. Levator scapulae
Correct Answer: B
Rationale:
The splenius capitis extends, rotates, and sidebends the head ipsilaterally.
Hypertonicity can restrict cervical rotation and contribute to headache patterns
commonly seen with upper cervical dysfunction.
,Question 2
A patient presents with confusion, ataxia, and ophthalmoplegia. Chronic alcohol
use is noted. Which biochemical process is most directly impaired?
A. DNA synthesis
B. Oxidative phosphorylation
C. Pyruvate dehydrogenase activity
D. Fatty acid β-oxidation
E. Heme synthesis
Correct Answer: C
Rationale:
Thiamine deficiency impairs pyruvate dehydrogenase, preventing conversion of
pyruvate to acetyl-CoA, leading to neurologic deficits seen in Wernicke
encephalopathy.
Question 3
A gram-positive, catalase-positive organism grows in clusters and produces
coagulase. Which virulence factor allows immune evasion?
A. Protein A
B. Lipoteichoic acid
C. Streptolysin O
D. IgA protease
E. M protein
Correct Answer: A
Rationale:
Protein A binds the Fc portion of IgG, preventing opsonization and phagocytosis, a
hallmark of Staphylococcus aureus.
,Question 4
A patient has hyperplasia of the zona fasciculata. Which hormone level is most
likely elevated?
A. Aldosterone
B. Cortisol
C. Androstenedione
D. Epinephrine
E. Renin
Correct Answer: B
Rationale:
The zona fasciculata produces cortisol. Hyperplasia leads to excess cortisol,
producing Cushingoid features.
Question 5
A newborn fails to pass meconium and develops abdominal distension. Biopsy
shows absence of ganglion cells in the colon. What embryologic structure failed to
migrate?
A. Neural tube
B. Mesoderm
C. Neural crest cells
D. Endoderm
E. Notochord
Correct Answer: C
Rationale:
Hirschsprung disease results from failure of neural crest cell migration into the
colon, causing aganglionic megacolon.
, Question 6
A patient with atrial fibrillation is started on a medication that prolongs phase 3 of
the cardiac action potential. Which ion channel is affected?
A. Sodium
B. Calcium
C. Potassium
D. Chloride
E. Magnesium
Correct Answer: C
Rationale:
Phase 3 repolarization is mediated by potassium efflux. Potassium channel
blockade prolongs repolarization and refractory period.
Question 7
Which viscerosomatic reflex level is most associated with gastric pathology?
A. T1–T4
B. T5–T9
C. T10–T12
D. L1–L2
E. S2–S4
Correct Answer: B
Rationale:
The stomach receives sympathetic innervation from T5–T9, commonly producing
viscerosomatic findings at these levels.
