Our heart is a pump. As it performs its pumping action, it sends blood to the entire body, thus enabling us to live. A heart-beat* is the contracting and relaxing of the heart. A human heart-beats around 60-100 times per minute approximately 1,00,000 times per day. As the heart contracts, blood is pumped out and when it relaxes, new blood enters the heart. A small electric impulse generated by the natural pacemaker present in the heart is what makes the heart-beat. There are two natural pacemakers present in the heart: the SA node which helps contract the atria and the AV node which helps control the contraction of ventricles. These pacemakers are the lifelines of the heart.
What Keeps the Heart-beating?
