ATI RN
Cardiovascular System Quiz Questions Questions
Question 1 of 5
This about second heart sound is incorrect
Correct Answer: D
Rationale: The second heart sound (S₂) results from semilunar valve closure (aortic and pulmonary) at the start of diastole and can split due to asynchronous closure (A and C are true). S₁ (AV valve closure) is longer and lower-pitched (~0.14s) than S₂ (~0.11s), making D incorrect as S₂ is shorter, not longer.
Question 2 of 5
The atrioventricular (AV) node is important for heart function because:
Correct Answer: D
Rationale: The AV node delays the impulse (C, ~0.1s) to allow atrial contraction before ventricular systole and directs it to the ventricles via the bundle of His (A). It’s not the pacemaker (B, that’s the SA node), so E (A and C) is correct.
Question 3 of 5
What structures anchor the AV (atrioventricular) valves to the walls of the ventricles?
Correct Answer: C
Rationale: Chordae tendineae (C) anchor AV valves (tricuspid, mitral) to papillary muscles in the ventricles, preventing prolapse into atria. The septum (A) divides ventricles, auricles (B) are atrial appendages, and endocardium (D) is the inner lining.
Question 4 of 5
The T wave on an ECG (EKG) represents:
Correct Answer: D
Rationale: The T wave (D) represents ventricular repolarization. Atrial depolarization is P wave (A), atrial repolarization is obscured by QRS, and ventricular depolarization is QRS (C).
Question 5 of 5
Frank Starlings law states that if more blood enters the heart,
Correct Answer: B
Rationale: Frank-Starling’s law states that increased preload (more blood) stretches cardiac muscle, leading to a stronger contraction (B) and greater stroke volume. A, C, D contradict this.