All of the following statements regarding the heart are true EXCEPT
The sinoatrial node receives a nerve supply; however, this node initiates the heartbeat autonomously. The autonomic innervation modulates the rate of depolar­ization of the sinoatrial node, thereby modulating the heart rate. The sinoatrial node is composed of special­ized cardiac muscle cells that depolarize spontaneously at a greater rate than that of other cardiac muscle cells. Because cardiac muscle cells contact each other electrically through gap junctions at the intercalated discs, the depolarization of the sinoatrial node drives the other cardiac muscle cells of the atrium to depolar­ize at the same rate as the node.
The nerve fibers that conduct the pain associated with ischemia accompany the sympathetic nerve supply to the heart
The sinoatrial node does not receive a nerve supply and thus initiates the heart beat autonomously
The atrioventricular node is located in the interatrial septum
The diaphragmatic surface of the heart is composed primarily of the left ventricular wall