Question
Why S.A. node is called pacemaker of heart?
Solution
The SA node or sino-atrial node (SAN) is called the the natural pacemaker of the heart. It controls the heart rate by generating electrical impulses and then sending electrical signals through the heart muscle, causing the heart to contract and pump blood throughout the body.The heart beat originates from S.A. node and spreads to the walls of auricles which contract.
