ATI RN
Cardiovascular System Questions and Answers Quizlet Questions
Question 1 of 5
This is the reason why the SA node acts as heart's pacemaker
Correct Answer: D
Rationale: The sinoatrial (SA) node is the heart’s pacemaker because it has the highest intrinsic rate of spontaneous depolarization (~60-100 beats/min), outpacing other cardiac cells (e.g., AV node: 40-60, Purkinje: 20-40). While it generates impulses (C), D specifies the rate, which is key. Cholinergic (parasympathetic) innervation slows it, and sympathetic innervation enhances it, but neither defines its pacemaker role.
Question 2 of 5
The rhythm and electrical activity of the heart can be detected with electrodes on the skin and displayed in the form of an:
Correct Answer: C
Rationale: An electrocardiogram (ECG, C) records the heart’s electrical activity via skin electrodes, showing rhythm and conduction. A (eye movement), B (brain activity), D (ultrasound imaging), and E (muscle activity) are unrelated to this function.
Question 3 of 5
Identify the blood vessel that carries blood from the left ventricle.
Correct Answer: A
Rationale: The aorta (A) carries oxygenated blood from the left ventricle to the body. The pulmonary artery (B) carries deoxygenated blood from the right ventricle, pulmonary vein (C) to the left atrium, and superior vena cava (D) to the right atrium.
Question 4 of 5
What wave of an ECG (EKG) represents depolarization of the atria?
Correct Answer: A
Rationale: The P wave (A) represents atrial depolarization. QRS (B) is ventricular depolarization, T wave (C) is ventricular repolarization, and PQ interval (D) is a time segment, not a wave.
Question 5 of 5
The sympathetic nervous system will ___ contraction strength of the heart, thus leading to a(n) ___ in stroke volume.
Correct Answer: C
Rationale: Sympathetic stimulation increases contraction strength (inotropy, C) via norepinephrine, increasing stroke volume. A, B, D mismatch physiology.