,South University NSG 3009 Exam 3 | Principles of
Assessment (2026) Q&A
1. Which structure is responsible for initiating the electrical impulse that sets the resting heart
rate?
A) Atrioventricular node
B) Sinoatrial node
C) Bundle of His
D) Purkinje fibers
Correct Answer: Sinoatrial node
Rationale: The sinoatrial (SA) node is the primary pacemaker of the heart, spontaneously
generating electrical impulses that initiate each heartbeat. The atrioventricular (AV) node delays
the impulse, the bundle of His and Purkinje fibers conduct the impulse to the ventricles, but the
SA node sets the rate.
2. What is the primary function of the atrioventricular (AV) valves during the cardiac cycle?
A) They prevent backflow of blood from the ventricles into the atria.
B) They prevent backflow of blood from the aorta into the left ventricle.
C) They regulate the flow of blood from the atria to the lungs.
D) They control the amount of blood ejected during systole.
Correct Answer: They prevent backflow of blood from the ventricles into the atria.
Rationale: The AV valves (tricuspid and mitral) separate the atria from the ventricles and close
during ventricular systole to prevent blood from flowing backward into the atria. The semilunar
valves (aortic and pulmonic) prevent backflow from the great arteries into the ventricles.
,3. Which finding is a normal age-related change in the cardiovascular system of an older adult?
A) Decreased systolic blood pressure
B) Increased resting heart rate
C) Decreased cardiac output at rest
D) Increased elasticity of the arterial walls
Correct Answer: Decreased cardiac output at rest
Rationale: Older adults experience decreased cardiac output at rest due to reduced stroke
volume and decreased maximal heart rate. Blood pressure often increases due to arterial
stiffening. Resting heart rate may decrease. Arterial walls lose elasticity, becoming stiff.
4. Which heart sound is associated with the closure of the semilunar valves?
A) S1
B) S2
C) S3
D) S4
Correct Answer: S2
Rationale: S2 is the "dub" sound caused by the closure of the semilunar valves (aortic and
pulmonic) at the end of ventricular systole. S1 is the "lub" sound caused by closure of the AV
valves. S3 and S4 are abnormal sounds that may indicate heart failure or ventricular stiffness.
5. What is the correct technique for auscultating the mitral valve area?
A) Second intercostal space at the right sternal border
B) Second intercostal space at the left sternal border
, C) Fifth intercostal space at the left midclavicular line
D) Fourth intercostal space at the left sternal border
Correct Answer: Fifth intercostal space at the left midclavicular line
Rationale: The mitral (bicuspid) valve is best heard at the apex of the heart, which is located at
the fifth intercostal space at the left midclavicular line (the point of maximal impulse). The aortic
valve is heard at the second right intercostal space, the pulmonic at the second left, and the
tricuspid at the fourth left sternal border.
6. Which finding suggests left-sided heart failure during a cardiovascular assessment?
A) Jugular venous distension
B) Peripheral edema
C) Crackles in the lung bases
D) Hepatomegaly
Correct Answer: Crackles in the lung bases
Rationale: Left-sided heart failure leads to pulmonary congestion, which causes crackles
(rales) in the lung bases, orthopnea, and paroxysmal nocturnal dyspnea. Jugular venous
distension, peripheral edema, and hepatomegaly are signs of right-sided heart failure.
7. What is the normal range for the point of maximal impulse (PMI) in an adult?
A) Third intercostal space at the left sternal border
B) Fourth intercostal space at the left midclavicular line
C) Fifth intercostal space at the left midclavicular line
D) Sixth intercostal space at the anterior axillary line
Assessment (2026) Q&A
1. Which structure is responsible for initiating the electrical impulse that sets the resting heart
rate?
A) Atrioventricular node
B) Sinoatrial node
C) Bundle of His
D) Purkinje fibers
Correct Answer: Sinoatrial node
Rationale: The sinoatrial (SA) node is the primary pacemaker of the heart, spontaneously
generating electrical impulses that initiate each heartbeat. The atrioventricular (AV) node delays
the impulse, the bundle of His and Purkinje fibers conduct the impulse to the ventricles, but the
SA node sets the rate.
2. What is the primary function of the atrioventricular (AV) valves during the cardiac cycle?
A) They prevent backflow of blood from the ventricles into the atria.
B) They prevent backflow of blood from the aorta into the left ventricle.
C) They regulate the flow of blood from the atria to the lungs.
D) They control the amount of blood ejected during systole.
Correct Answer: They prevent backflow of blood from the ventricles into the atria.
Rationale: The AV valves (tricuspid and mitral) separate the atria from the ventricles and close
during ventricular systole to prevent blood from flowing backward into the atria. The semilunar
valves (aortic and pulmonic) prevent backflow from the great arteries into the ventricles.
,3. Which finding is a normal age-related change in the cardiovascular system of an older adult?
A) Decreased systolic blood pressure
B) Increased resting heart rate
C) Decreased cardiac output at rest
D) Increased elasticity of the arterial walls
Correct Answer: Decreased cardiac output at rest
Rationale: Older adults experience decreased cardiac output at rest due to reduced stroke
volume and decreased maximal heart rate. Blood pressure often increases due to arterial
stiffening. Resting heart rate may decrease. Arterial walls lose elasticity, becoming stiff.
4. Which heart sound is associated with the closure of the semilunar valves?
A) S1
B) S2
C) S3
D) S4
Correct Answer: S2
Rationale: S2 is the "dub" sound caused by the closure of the semilunar valves (aortic and
pulmonic) at the end of ventricular systole. S1 is the "lub" sound caused by closure of the AV
valves. S3 and S4 are abnormal sounds that may indicate heart failure or ventricular stiffness.
5. What is the correct technique for auscultating the mitral valve area?
A) Second intercostal space at the right sternal border
B) Second intercostal space at the left sternal border
, C) Fifth intercostal space at the left midclavicular line
D) Fourth intercostal space at the left sternal border
Correct Answer: Fifth intercostal space at the left midclavicular line
Rationale: The mitral (bicuspid) valve is best heard at the apex of the heart, which is located at
the fifth intercostal space at the left midclavicular line (the point of maximal impulse). The aortic
valve is heard at the second right intercostal space, the pulmonic at the second left, and the
tricuspid at the fourth left sternal border.
6. Which finding suggests left-sided heart failure during a cardiovascular assessment?
A) Jugular venous distension
B) Peripheral edema
C) Crackles in the lung bases
D) Hepatomegaly
Correct Answer: Crackles in the lung bases
Rationale: Left-sided heart failure leads to pulmonary congestion, which causes crackles
(rales) in the lung bases, orthopnea, and paroxysmal nocturnal dyspnea. Jugular venous
distension, peripheral edema, and hepatomegaly are signs of right-sided heart failure.
7. What is the normal range for the point of maximal impulse (PMI) in an adult?
A) Third intercostal space at the left sternal border
B) Fourth intercostal space at the left midclavicular line
C) Fifth intercostal space at the left midclavicular line
D) Sixth intercostal space at the anterior axillary line
