Which of the following statements is true regarding parasympathetic tone?
A) It holds the resting heart rate below its intrinsic rate.
B) It accelerates the resting heart rate above its intrinsic rate.
C) It might increase or decrease heart rate depending on the situation.
D) It affects heart rate only after myocardial infarction.
E) It does not affect heart rate.

Question

Quizplus · Accepted Answer

Parasympathetic tone is responsible for regulating the resting heart rate and keeping it below its intrinsic rate. It achieves this through the release of acetylcholine, which decreases the heart rate by slowing down the firing of the sinoatrial node. If parasympathetic tone is decreased or inhibited, heart rate can increase.

Which of the Following Statements Is True Regarding Parasympathetic Tone