Answer:
The correct answer to the question: The structure which is the pacemaker of the heart is:____, would be, C: The SA node.
Explanation:
The heart has an autonomic, and automatic, electrical system that is responsible for the heart being able to perform its functions. This structure, known as the conducting system of the heart, is formed by a series of specialized neural cells capable of generating and conducting electrical charges that stimulate the myochardial cells, and activate them, so that they will contract and relax during a heart cycle. The starting point of this conducting system, is the SA node, at the atria of the heart. It will be the neural cells in the SA node which will autonomically, and automatically generate an electrical current that will move downwards in the same way as it happens in the nervous system, towards the AV node at the top of the ventricles, then down towards the bundle of His and finally to the Purkinje fibers. Therefore, the SA node is known as the pacemaker of the heart.
