Comprehensive Exam: BIOS255 / BIOS 255
ACTUAL EXAM 2026/2027 | Anatomy and
Physiology III with Lab | Verified Q&A |
Pass Guaranteed - A+ Graded
Section 1: Cardiovascular System (Q1–Q20)
Q1: Which chamber of the heart receives oxygenated blood from the lungs?
A. Right atrium
B. Right ventricle
C. Left atrium. [CORRECT]
D. Left ventricle
Correct Answer: C
Rationale: The left atrium receives oxygenated blood via the pulmonary veins. Students often confuse
this with the right atrium (A), which receives deoxygenated blood from the systemic circulation via the
vena cavae. The left ventricle (D) receives blood from the left atrium and pumps it to the body. The right
ventricle (B) pumps deoxygenated blood to the lungs. Nursing relevance: Understanding blood flow is
essential for interpreting murmurs, heart sounds, and cardiac catheterization reports.
Q2: The bicuspid (mitral) valve is located between the:
A. Right atrium and right ventricle
B. Left atrium and left ventricle. [CORRECT]
C. Right ventricle and pulmonary trunk
D. Left ventricle and aorta
Correct Answer: B
,Rationale: The bicuspid (mitral) valve separates the left atrium from the left ventricle. The tricuspid
valve is between the right atrium and right ventricle (A)—students frequently confuse these. The
pulmonary valve (C) and aortic valve (D) are semilunar valves. Nursing relevance: Mitral regurgitation
causes a holosystolic murmur at the apex; mitral stenosis produces an opening snap and diastolic
rumble.
Q3: During ventricular systole, which heart valves are closed?
A. AV valves only
B. Semilunar valves only
C. Both AV and semilunar valves
D. AV valves are closed and semilunar valves are open. [CORRECT]
Correct Answer: D
Rationale: During ventricular systole, ventricular pressure rises above atrial pressure (closing AV valves)
and exceeds arterial pressure (opening semilunar valves). Students often think all valves close
simultaneously (C), but this would trap blood in the ventricle with no ejection. AV valves only (A)
describes isovolumetric contraction specifically, not all of systole. Nursing relevance: Understanding
valve timing explains heart sounds (S1 = AV closure, S2 = semilunar closure) and murmur timing.
Q4: The P wave on an ECG represents:
A. Ventricular depolarization
B. Ventricular repolarization
C. Atrial depolarization. [CORRECT]
D. Atrial repolarization
Correct Answer: C
Rationale: The P wave represents atrial depolarization (electrical activation). Ventricular depolarization
(A) is the QRS complex. Ventricular repolarization (B) is the T wave. Atrial repolarization (D) is usually
hidden within the QRS complex and not visible on standard ECG. Nursing relevance: Absent P waves
indicate atrial fibrillation or junctional rhythms; peaked P waves suggest right atrial enlargement.
Q5: Which factor would increase cardiac output (CO = HR × SV)?
, A. Increased parasympathetic stimulation
B. Decreased venous return
C. Increased sympathetic stimulation. [CORRECT]
D. Decreased contractility
Correct Answer: C
Rationale: Sympathetic stimulation increases heart rate and contractility (stroke volume), thereby
increasing cardiac output. Parasympathetic stimulation (A) decreases heart rate. Decreased venous
return (B) reduces preload and stroke volume. Decreased contractility (D) reduces stroke volume.
Students often confuse sympathetic and parasympathetic effects on the heart. Nursing relevance: In
shock, sympathetic activation compensates by increasing CO; beta-blockers inhibit this response.
Q6: Which blood vessel has the thickest tunica media relative to its lumen size?
A. Vena cava
B. Large vein
C. Muscular artery. [CORRECT]
D. Capillary
Correct Answer: C
Rationale: Muscular (distributing) arteries have the thickest tunica media relative to lumen size,
containing abundant smooth muscle for vasoconstriction/vasodilation. Vena cava (A) and large veins (B)
have thin walls with large lumens. Capillaries (D) have only an endothelium. Students often think
arteries are all similar; the relative thickness matters for function. Nursing relevance: Muscular arteries
regulate blood flow distribution; atherosclerosis in these vessels causes hypertension and organ
ischemia.
Q7: Blood pressure is highest in which vessel during systole?
A. Capillaries
B. Venules
C. Aorta. [CORRECT]
D. Pulmonary veins
, Correct Answer: C
Rationale: The aorta experiences the highest pressure during ventricular systole as it receives blood
ejected from the left ventricle. Pressure decreases progressively through the circulation: arteries >
arterioles > capillaries > venules > veins. Students sometimes think capillaries (A) have high pressure, but
their total cross-sectional area reduces pressure. Nursing relevance: Aortic pressure measurement is the
basis for systemic blood pressure; aortic aneurysm rupture causes rapid exsanguination.
Q8: Which structure prevents backflow of blood from the right ventricle into the right atrium?
A. Aortic semilunar valve
B. Pulmonary semilunar valve
C. Tricuspid valve. [CORRECT]
D. Mitral valve
Correct Answer: C
Rationale: The tricuspid valve prevents backflow from the right ventricle to the right atrium. The mitral
valve (D) is on the left side. The aortic (A) and pulmonary (B) semilunar valves prevent backflow from
arteries into ventricles. Students frequently confuse left and right heart valves. Nursing relevance:
Tricuspid regurgitation causes elevated jugular venous pressure with prominent v waves and hepatic
congestion.
Q9: The T wave on an ECG corresponds to which electrical event?
A. Atrial depolarization
B. Ventricular depolarization
C. Ventricular repolarization. [CORRECT]
D. Atrial repolarization
Correct Answer: C
Rationale: The T wave represents ventricular repolarization (electrical recovery). Atrial depolarization
(A) is the P wave. Ventricular depolarization (B) is the QRS complex. Atrial repolarization (D) is not
normally visible. Nursing relevance: T wave inversion or elevation indicates myocardial ischemia or
infarction; peaked T waves suggest hyperkalemia.
ACTUAL EXAM 2026/2027 | Anatomy and
Physiology III with Lab | Verified Q&A |
Pass Guaranteed - A+ Graded
Section 1: Cardiovascular System (Q1–Q20)
Q1: Which chamber of the heart receives oxygenated blood from the lungs?
A. Right atrium
B. Right ventricle
C. Left atrium. [CORRECT]
D. Left ventricle
Correct Answer: C
Rationale: The left atrium receives oxygenated blood via the pulmonary veins. Students often confuse
this with the right atrium (A), which receives deoxygenated blood from the systemic circulation via the
vena cavae. The left ventricle (D) receives blood from the left atrium and pumps it to the body. The right
ventricle (B) pumps deoxygenated blood to the lungs. Nursing relevance: Understanding blood flow is
essential for interpreting murmurs, heart sounds, and cardiac catheterization reports.
Q2: The bicuspid (mitral) valve is located between the:
A. Right atrium and right ventricle
B. Left atrium and left ventricle. [CORRECT]
C. Right ventricle and pulmonary trunk
D. Left ventricle and aorta
Correct Answer: B
,Rationale: The bicuspid (mitral) valve separates the left atrium from the left ventricle. The tricuspid
valve is between the right atrium and right ventricle (A)—students frequently confuse these. The
pulmonary valve (C) and aortic valve (D) are semilunar valves. Nursing relevance: Mitral regurgitation
causes a holosystolic murmur at the apex; mitral stenosis produces an opening snap and diastolic
rumble.
Q3: During ventricular systole, which heart valves are closed?
A. AV valves only
B. Semilunar valves only
C. Both AV and semilunar valves
D. AV valves are closed and semilunar valves are open. [CORRECT]
Correct Answer: D
Rationale: During ventricular systole, ventricular pressure rises above atrial pressure (closing AV valves)
and exceeds arterial pressure (opening semilunar valves). Students often think all valves close
simultaneously (C), but this would trap blood in the ventricle with no ejection. AV valves only (A)
describes isovolumetric contraction specifically, not all of systole. Nursing relevance: Understanding
valve timing explains heart sounds (S1 = AV closure, S2 = semilunar closure) and murmur timing.
Q4: The P wave on an ECG represents:
A. Ventricular depolarization
B. Ventricular repolarization
C. Atrial depolarization. [CORRECT]
D. Atrial repolarization
Correct Answer: C
Rationale: The P wave represents atrial depolarization (electrical activation). Ventricular depolarization
(A) is the QRS complex. Ventricular repolarization (B) is the T wave. Atrial repolarization (D) is usually
hidden within the QRS complex and not visible on standard ECG. Nursing relevance: Absent P waves
indicate atrial fibrillation or junctional rhythms; peaked P waves suggest right atrial enlargement.
Q5: Which factor would increase cardiac output (CO = HR × SV)?
, A. Increased parasympathetic stimulation
B. Decreased venous return
C. Increased sympathetic stimulation. [CORRECT]
D. Decreased contractility
Correct Answer: C
Rationale: Sympathetic stimulation increases heart rate and contractility (stroke volume), thereby
increasing cardiac output. Parasympathetic stimulation (A) decreases heart rate. Decreased venous
return (B) reduces preload and stroke volume. Decreased contractility (D) reduces stroke volume.
Students often confuse sympathetic and parasympathetic effects on the heart. Nursing relevance: In
shock, sympathetic activation compensates by increasing CO; beta-blockers inhibit this response.
Q6: Which blood vessel has the thickest tunica media relative to its lumen size?
A. Vena cava
B. Large vein
C. Muscular artery. [CORRECT]
D. Capillary
Correct Answer: C
Rationale: Muscular (distributing) arteries have the thickest tunica media relative to lumen size,
containing abundant smooth muscle for vasoconstriction/vasodilation. Vena cava (A) and large veins (B)
have thin walls with large lumens. Capillaries (D) have only an endothelium. Students often think
arteries are all similar; the relative thickness matters for function. Nursing relevance: Muscular arteries
regulate blood flow distribution; atherosclerosis in these vessels causes hypertension and organ
ischemia.
Q7: Blood pressure is highest in which vessel during systole?
A. Capillaries
B. Venules
C. Aorta. [CORRECT]
D. Pulmonary veins
, Correct Answer: C
Rationale: The aorta experiences the highest pressure during ventricular systole as it receives blood
ejected from the left ventricle. Pressure decreases progressively through the circulation: arteries >
arterioles > capillaries > venules > veins. Students sometimes think capillaries (A) have high pressure, but
their total cross-sectional area reduces pressure. Nursing relevance: Aortic pressure measurement is the
basis for systemic blood pressure; aortic aneurysm rupture causes rapid exsanguination.
Q8: Which structure prevents backflow of blood from the right ventricle into the right atrium?
A. Aortic semilunar valve
B. Pulmonary semilunar valve
C. Tricuspid valve. [CORRECT]
D. Mitral valve
Correct Answer: C
Rationale: The tricuspid valve prevents backflow from the right ventricle to the right atrium. The mitral
valve (D) is on the left side. The aortic (A) and pulmonary (B) semilunar valves prevent backflow from
arteries into ventricles. Students frequently confuse left and right heart valves. Nursing relevance:
Tricuspid regurgitation causes elevated jugular venous pressure with prominent v waves and hepatic
congestion.
Q9: The T wave on an ECG corresponds to which electrical event?
A. Atrial depolarization
B. Ventricular depolarization
C. Ventricular repolarization. [CORRECT]
D. Atrial repolarization
Correct Answer: C
Rationale: The T wave represents ventricular repolarization (electrical recovery). Atrial depolarization
(A) is the P wave. Ventricular depolarization (B) is the QRS complex. Atrial repolarization (D) is not
normally visible. Nursing relevance: T wave inversion or elevation indicates myocardial ischemia or
infarction; peaked T waves suggest hyperkalemia.
