_______ Increases Heart Rate

Question

_______ increases heart rate.
A) Relaxation
B) Norepinephrine
C) Acetylcholine
D) Subnormal temperatures

Accepted Answer

Norepinephrine is a hormone that is released by the sympathetic nervous system in response to stress or physical activity, and it increases heart rate by binding to beta-adrenergic receptors in the heart. Relaxation, acetylcholine, and subnormal temperatures generally have the opposite effect on heart rate.