The _____ has the fastest rate of depolarization and therefore directs all the other cells of the heart.

Question

Quizplus · Accepted Answer

The SA node has the fastest rate of depolarization and therefore directs all the other cells of the heart.It normally fires impulses approximately 80 times per minute.The SA node is innervated by both the parasympathetic nervous system and the sympathetic nervous system.The SA node sends a message to the AV node via the atrial muscle.The AV node sends the message via the bundle of His to the Purkinje fibers.The Purkinje fibers then send the message to the cardiac muscle cells,to the apex of the ventricles,directing them all to contract as they get the message.

The _____ Has the Fastest Rate of Depolarization and Therefore