Answer:
a) True
Explanation:
The heart contains cardiac autorhythmic muscle cells, which are specialized cells that generate their own action potential without the need to receive it from nerve cells. These self-stimulated or self-excitable cells work together and function as the heart's natural pacemaker, which initiates an electric potential at a constant rate, and this potential travels through the heart triggering its contraction in an organized manner called the cardiac cycle.
These autorhythmic cells are found in the SA (sinoatrial) node in the right atrium of the heart, the AV (atrioventricular) node in between the atria and the ventricles, and in the fibers that connect these two nodes with each other and with the rest of the heart. All these structure working together is what's called the heart's electrical system.