A certain drug decreases heart rate by blocking a receptor on cardiac pacemaker cells. This drug probably binds to_____ receptors.
A) muscarinic cholinergic
B) alpha- 2 adrenergic
C) beta- 1 adrenergic
D) nicotinic cholinergic
E) alpha- 1 adrenergic

Question

Quizplus · Accepted Answer

Beta-1 adrenergic receptors are primarily found in the heart and are responsible for increasing heart rate and contractility. Blocking these receptors would decrease heart rate.

A Certain Drug Decreases Heart Rate by Blocking a Receptor