Body Fluids and Circulation Question 71
71. The cardiac pacemaker in a patient fails to function normally. The doctors find that an artificial pacemaker is to be grafted in him. It is likely that it will be grafted at the site of
(a) Atrioventricular bundle
(b) Purkinje system
(c) Sinuatrial node
(d) Atrioventricular node
Show Answer
Answer : c
Hints & Solutions
(c) SA node is the natural pacemaker located in the right atrium. SA node initiates the cardiac impulse. So, artificial pacemaker will be grafted at the site of SA node. $SA$ is located at the junction of the crista terminalis in the upper wall of the right atrium and the opening of the superior vena cava. These cells have the ability to spontaneous generate an electrical impulse. It is the integrated activity of these so-called pacemaker (P) cells that form the SA node..
