Question

n the heart, an action potential originates in the
multiple choice
subendocardial branches (purkinje fibers)
bundle branches
atrioventricular bundle
atrioventricular node
sinuatrial node

Explanation:

The sinoatrial (SA) node is known as the "pacemaker" of the heart. It generates electrical impulses (action potentials) that initiate the heartbeat. The atrioventricular (AV) node, atrioventricular bundle, bundle branches, and subendocardial branches (Purkinje fibers) are part of the conduction system but do not originate the action potential. The AV node receives impulses from the SA node, the atrioventricular bundle (bundle of His) transmits impulses from the AV node, the bundle branches further distribute the impulses, and the Purkinje fibers conduct the impulses to the ventricular muscle cells.

Answer:

sinusatrial node