Which part of the human heart is called the pacemaker because it starts and keeps up the rhythmic beating of the heart?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Sino-atrial node
The sino-atrial node (SAN), in the upper right corner of the right atrium, produces the largest number of impulses and starts each heartbeat. So it is called the pacemaker; the atrio-ventricular node and the bundle of His carry the impulse on to the ventricles.