19.5 Anatomic Structures Controlling Heart Activity

Question 1

sinoatrial (SA) node

Answer 1

• pacemaker of the heart
• posterior wall of the right atrium by the entrance of the SVC

Question 2

atrioventricular (AV) node

Answer 2

• bottom of the right atrium between the right AV valve and the opening of the coronary sinus
• coordinates the “lub” and the “dub”

Question 3

atrioventricular (AV) bundle

Answer 3

• form AV node through the interventricular septum
• divides the left + right bundle branches
• makes sure the chambers beat seperately

Question 4

purkinje fibers

Answer 4

• apex of the the heart through the walls of the ventricles
• helps the ventricles contract