ATI RN
100 Questions on the Cardiovascular System Questions
Question 1 of 5
The ventricular muscles accept impulses directly from
Correct Answer: D
Rationale: The Purkinje fibers deliver impulses directly to ventricular myocardium, causing rapid, coordinated contraction. The AV node delays the signal, the Bundle of His splits it, and bundle branches distribute it, but Purkinje fibers are the final step to the muscle.
Question 2 of 5
Identify the vessel(s) that return blood to the left atrium.
Correct Answer: D
Rationale: The left atrium receives oxygenated blood from the lungs via the right and left pulmonary veins (D). The coronary sinus (A, B) drains to the right atrium, and the pulmonary trunk (C) is an artery from the right ventricle.
Question 3 of 5
Which of the following is NOT true of atherosclerosis?
Correct Answer: D
Rationale: Atherosclerosis is caused by endothelial injury (D is false), leading to plaque formation. Smoking (A), insulin-dependent diabetes mellitus (C), and possibly H. pylori (B, via inflammation) are risk factors.
Question 4 of 5
What causes the semilunar valves to open?
Correct Answer: B
Rationale: Semilunar valves open when ventricular pressure exceeds arterial pressure (B, ~80 mmHg diastolic) during systole. A is the result, C/D don’t open valves.
Question 5 of 5
Place the layers of a blood vessel in order from innermost to outermost layer.
Correct Answer: D
Rationale: Blood vessel layers from innermost to outermost are: tunica intima, tunica media, tunica externa (D). A, B, C reverse or misorder the sequence.