COMSAE Phase 1 Form 116 (2026–2027) |
Complete 150-Question COMLEX Level 1–Style
Practice Exam with Detailed Explanations and
High-Yield Review Guide
Overview
This comprehensive COMSAE Phase 1 Form 116–Style Practice Exam is designed to help osteopathic
medical students prepare for COMLEX-USA Level 1 by reinforcing foundational biomedical sciences,
systems-based pathology, pharmacology, and osteopathic clinical reasoning. The practice set includes 150
original, exam-style multiple-choice questions with detailed explanations that mirror the integrated,
vignette-based approach commonly encountered on osteopathic board examinations.
The questions emphasize critical thinking, application of basic science principles to clinical scenarios, and
high-yield concepts frequently reviewed during COMLEX Level 1 preparation. Each item is intended to
strengthen test-taking skills, identify knowledge gaps, and improve readiness for comprehensive
osteopathic licensing examinations.
Coverage
Cardiovascular physiology, pathology, and electrocardiogram interpretation
Neurology, neuroanatomy, and neurologic disorders
Respiratory diseases and pulmonary physiology
Renal physiology, electrolyte disorders, and acid-base disturbances
Gastrointestinal physiology and pathology
Endocrinology and metabolic disorders
Hematology, coagulation, and oncology principles
Microbiology, infectious diseases, and antimicrobial pharmacology
Immunology, hypersensitivity reactions, and immunodeficiency disorders
General and autonomic pharmacology
Musculoskeletal medicine and osteopathic principles
Genetics, embryology, and molecular biology
Ethics, professionalism, and integrated clinical reasoning
High-yield multi-system clinical vignettes modeled after COMLEX Level 1 testing domains
Original questions inspired by commonly tested COMLEX Level 1 topics and blueprint
domains. These are not actual COMSAE Form 116 questions.
,1.
A 68-year-old man presents with crushing substernal chest pain radiating to his left arm for
45 minutes. Electrocardiography demonstrates ST-segment elevations in leads II, III, and
aVF. Occlusion of which coronary vessel is most likely responsible for this patient's
presentation?
A. Left anterior descending artery
B. Left circumflex artery
C. Posterior interventricular branch of right coronary artery
D. Left main coronary artery
E. Diagonal branch of left anterior descending artery
Answer: C
Explanation: ST-segment elevations in leads II, III, and aVF indicate an inferior wall
myocardial infarction, most commonly due to occlusion of the right coronary artery or its
posterior interventricular branch.
2.
A 22-year-old college student develops fever, headache, neck stiffness, and photophobia.
Cerebrospinal fluid analysis shows elevated neutrophils, decreased glucose, and increased
protein. Which organism is most likely responsible?
A. Streptococcus pneumoniae
B. Listeria monocytogenes
C. Neisseria meningitidis
D. Herpes simplex virus type 1
E. Cryptococcus neoformans
Answer: C
Explanation: Young adults living in close quarters are at increased risk for
meningococcal meningitis caused by Neisseria meningitidis.
3.
,A researcher administers a drug that competitively inhibits angiotensin-converting enzyme.
Which physiological change is most likely to occur?
A. Increased angiotensin II production
B. Increased aldosterone secretion
C. Increased peripheral vascular resistance
D. Decreased bradykinin degradation
E. Increased sodium retention
Answer: D
Explanation: ACE inhibitors decrease conversion of angiotensin I to angiotensin II and
inhibit bradykinin breakdown, increasing bradykinin levels.
4.
A newborn develops bilious vomiting shortly after birth. Imaging demonstrates failure of
recanalization of the intestinal lumen. Which embryologic structure is most likely affected?
A. Midgut
B. Hindgut
C. Neural tube
D. Foregut
E. Cloacal membrane
Answer: A
Explanation: Duodenal atresia commonly results from failure of recanalization and
affects a structure derived from the foregut-midgut junction.
5.
A patient with poorly controlled diabetes mellitus has elevated hemoglobin A1c
concentrations. Hemoglobin A1c results from which biochemical process?
A. Phosphorylation
B. Acetylation
C. Glycosylation
, D. Carboxylation
E. Sulfation
Answer: C
Explanation: Hemoglobin A1c forms through nonenzymatic glycosylation of
hemoglobin by circulating glucose.
6.
A patient suffers trauma to the radial nerve within the spiral groove of the humerus. Which
physical examination finding is most likely present?
A. Loss of thumb opposition
B. Inability to abduct fingers
C. Inability to flex the elbow
D. Wrist drop
E. Loss of shoulder abduction
Answer: D
Explanation: Radial nerve injury commonly causes weakness of wrist and finger
extension, producing wrist drop.
7.
A patient presents with episodic wheezing and shortness of breath. Administration of an
inhaled beta-2 agonist results in bronchodilation through which intracellular mechanism?
A. Increased intracellular calcium
B. Decreased cyclic AMP
C. Increased cyclic AMP
D. Inhibition of phospholipase C
E. Increased IP3 production
Answer: C
Explanation: Beta-2 receptor stimulation activates Gs proteins, increasing cyclic AMP
and causing smooth muscle relaxation.
Complete 150-Question COMLEX Level 1–Style
Practice Exam with Detailed Explanations and
High-Yield Review Guide
Overview
This comprehensive COMSAE Phase 1 Form 116–Style Practice Exam is designed to help osteopathic
medical students prepare for COMLEX-USA Level 1 by reinforcing foundational biomedical sciences,
systems-based pathology, pharmacology, and osteopathic clinical reasoning. The practice set includes 150
original, exam-style multiple-choice questions with detailed explanations that mirror the integrated,
vignette-based approach commonly encountered on osteopathic board examinations.
The questions emphasize critical thinking, application of basic science principles to clinical scenarios, and
high-yield concepts frequently reviewed during COMLEX Level 1 preparation. Each item is intended to
strengthen test-taking skills, identify knowledge gaps, and improve readiness for comprehensive
osteopathic licensing examinations.
Coverage
Cardiovascular physiology, pathology, and electrocardiogram interpretation
Neurology, neuroanatomy, and neurologic disorders
Respiratory diseases and pulmonary physiology
Renal physiology, electrolyte disorders, and acid-base disturbances
Gastrointestinal physiology and pathology
Endocrinology and metabolic disorders
Hematology, coagulation, and oncology principles
Microbiology, infectious diseases, and antimicrobial pharmacology
Immunology, hypersensitivity reactions, and immunodeficiency disorders
General and autonomic pharmacology
Musculoskeletal medicine and osteopathic principles
Genetics, embryology, and molecular biology
Ethics, professionalism, and integrated clinical reasoning
High-yield multi-system clinical vignettes modeled after COMLEX Level 1 testing domains
Original questions inspired by commonly tested COMLEX Level 1 topics and blueprint
domains. These are not actual COMSAE Form 116 questions.
,1.
A 68-year-old man presents with crushing substernal chest pain radiating to his left arm for
45 minutes. Electrocardiography demonstrates ST-segment elevations in leads II, III, and
aVF. Occlusion of which coronary vessel is most likely responsible for this patient's
presentation?
A. Left anterior descending artery
B. Left circumflex artery
C. Posterior interventricular branch of right coronary artery
D. Left main coronary artery
E. Diagonal branch of left anterior descending artery
Answer: C
Explanation: ST-segment elevations in leads II, III, and aVF indicate an inferior wall
myocardial infarction, most commonly due to occlusion of the right coronary artery or its
posterior interventricular branch.
2.
A 22-year-old college student develops fever, headache, neck stiffness, and photophobia.
Cerebrospinal fluid analysis shows elevated neutrophils, decreased glucose, and increased
protein. Which organism is most likely responsible?
A. Streptococcus pneumoniae
B. Listeria monocytogenes
C. Neisseria meningitidis
D. Herpes simplex virus type 1
E. Cryptococcus neoformans
Answer: C
Explanation: Young adults living in close quarters are at increased risk for
meningococcal meningitis caused by Neisseria meningitidis.
3.
,A researcher administers a drug that competitively inhibits angiotensin-converting enzyme.
Which physiological change is most likely to occur?
A. Increased angiotensin II production
B. Increased aldosterone secretion
C. Increased peripheral vascular resistance
D. Decreased bradykinin degradation
E. Increased sodium retention
Answer: D
Explanation: ACE inhibitors decrease conversion of angiotensin I to angiotensin II and
inhibit bradykinin breakdown, increasing bradykinin levels.
4.
A newborn develops bilious vomiting shortly after birth. Imaging demonstrates failure of
recanalization of the intestinal lumen. Which embryologic structure is most likely affected?
A. Midgut
B. Hindgut
C. Neural tube
D. Foregut
E. Cloacal membrane
Answer: A
Explanation: Duodenal atresia commonly results from failure of recanalization and
affects a structure derived from the foregut-midgut junction.
5.
A patient with poorly controlled diabetes mellitus has elevated hemoglobin A1c
concentrations. Hemoglobin A1c results from which biochemical process?
A. Phosphorylation
B. Acetylation
C. Glycosylation
, D. Carboxylation
E. Sulfation
Answer: C
Explanation: Hemoglobin A1c forms through nonenzymatic glycosylation of
hemoglobin by circulating glucose.
6.
A patient suffers trauma to the radial nerve within the spiral groove of the humerus. Which
physical examination finding is most likely present?
A. Loss of thumb opposition
B. Inability to abduct fingers
C. Inability to flex the elbow
D. Wrist drop
E. Loss of shoulder abduction
Answer: D
Explanation: Radial nerve injury commonly causes weakness of wrist and finger
extension, producing wrist drop.
7.
A patient presents with episodic wheezing and shortness of breath. Administration of an
inhaled beta-2 agonist results in bronchodilation through which intracellular mechanism?
A. Increased intracellular calcium
B. Decreased cyclic AMP
C. Increased cyclic AMP
D. Inhibition of phospholipase C
E. Increased IP3 production
Answer: C
Explanation: Beta-2 receptor stimulation activates Gs proteins, increasing cyclic AMP
and causing smooth muscle relaxation.
