Body Fluids and Circulation Question 74
74. Impulse of heart beat originates from [2002]
(a) S. A. node
(b) A. V. node
(c) Vagus nerve
(d) Cardiac nerve
Show Answer
Answer : a
Hints & Solutions
(a) SAnode is called the pacemaker because it initiates the cardiac impulse. AV node receives the impulse from the SA node and transmits it to the ventricles.