Question

The “pacemaker” of the heart starts an electrical impulse in the right atrium to cause the atria to contract. What is the “pacemaker” of the heart?

the SA node
the AV node
the bundle of His
the Purkinje fibers

Answer 1

Hello!! The answer would be A - The SA node. It is known as the "pacemaker" because it initiates the heart's rhythmic contractions. I hope I helped!! Have a great day. :)

Answer 2

The correct answer is "the SA node".

Step-by-step explanation:

The heart beat is triggered by electrical impulses and among them, the sinoatrial node (SA node) is the one that receives the name of the “pacemaker” of the heart. The impulse of the SA node begins with a bundle in the right atrium, which spreads through the walls of the atria and causes a contraction. The SA node is the principal factor that affects the rate and rhythm of the heartbeat.