Question
Biology Question on neural control and coordination
The sino-atrial node is the normal pacemaker of the human heart because:
(A) It is located in the right atrium
(B) It is the only part of the conducting system that can generate impulse
(C) It can generate the maximum number of action potentials in the conducting system
(D) It produces action potentials that are more in size than the other parts of the conducting system
(C) It can generate the maximum number of action potentials in the conducting system
Solution
Explanation:
The sino-atrial node is the normal pacemaker of the human heart because it can generate the maximum number of action potentials in the conducting system.The sinus node continuously generates electrical impulses, thereby setting the normal rhythm and rate in a healthy heart. The sinoatrial node (SAN) is the natural pacemaker of the heart that determines heart rate in mammals, including humans. It is characterized by the ability to generate spontaneous action potentials that serve to excite the surrounding atrial myocardium.Hence, the correct option is (C).