The first part of the heart’s conduction system is the:%0D%0A%0D%0A(1 point)%0D%0AResponses%0D%0A%0D%0Asinoatrial node.%0D%0A%0D%0Asinoatrial node.%0D%0A%0D%0Aatrioventricular node.%0D%0A%0D%0Aatrioventricular node.%0D%0A%0D%0Amyocardial node.%0D%0A%0D%0Amyocardial node.%0D%0A%0D%0Aseptum node.