ATI RN
Cardiovascular System Questions Questions
Question 1 of 5
Stimulation of baroreceptor leads to:
Correct Answer: B
Rationale: Baroreceptor stimulation (e.g., high BP) triggers parasympathetic activation, lowering BP and heart rate (B). A and C increase BP, D is mixed.
Question 2 of 5
Identify the groove found on the surface of the heart and marks the boundary between the right and left ventricles.
Correct Answer: B
Rationale: The anterior interventricular sulcus (B) marks the boundary between the right and left ventricles on the heart’s front. Coronary sulcus (A) separates atria from ventricles, posterior sulcus (C) is on the back, and coronary sinus (D) is a vein.
Question 3 of 5
Which structure in the heart initiates action potentials that stimulate contraction of the heart at constant rate of about 100 beats per minute?
Correct Answer: D
Rationale: The SA node (D) initiates action potentials at ~100 bpm, though vagal tone slows it to 60-80 bpm in vivo. AV node (B) is slower (~40-60 bpm), nerves (A) and center (C) modulate.
Question 4 of 5
All of the following will increase heart rate except:
Correct Answer: C
Rationale: Parasympathetic stimulation (C) (vagus nerve) slows heart rate; others increase it via sympathetic or reflex mechanisms.
Question 5 of 5
The tough, loose-fitting outer layer of the sac covering the heart
Correct Answer: C
Rationale: The parietal pericardium (C) is the tough outer layer of the pericardial sac. Epicardium (A) and visceral pericardium (B) are on the heart, myocardium (D) is muscle.