The Heart Muscle is Said to Have Automaticity, Which Means

Question

The heart muscle is said to have automaticity, which means that .
A) the heart has a built-in automatic nerve
B) the heart muscle beats in a regular rhythm
C) the heart muscle depolarizes and contracts spontaneously without external stimulation
D) the nerves that innervate the heart cause the heart to beat automatically

Accepted Answer

The heart muscle, particularly the cells in the sinoatrial node, has the ability to depolarize and contract spontaneously without needing signals from the nervous system, which is what is meant by automaticity.