What is electrical firing mechanism of the heart?

The process of contraction and relaxation to pump blood to heart by atria and ventricles together is called electrical firing mechanism of the heart.

The electrical system regulates the timing of heartbeat through sending electrical signal.

The electrical signal originates in a group of cells at the top of heart known as  sinoatrial (SA) node and send the signal to right and left atria that triggers the atria muscles to get contract. after atria contraction the blood transfer to left and right ventricles and electrical signal arrives at atrioventricular node (AV node) that slows down the electrical signal and provide time to receive blood from atria to ventricles. electrical signal then move to ventricle muscles and allow them to contract. The left ventricle pumps blood to all body parts and right ventricle pumps blood to lungs.

After contraction of both atria and ventricles the electrical mechanism resets itself and follows the same process again.

it will take around no amount of ruffe to knock over this 110lbs man because he semms to be around 300lbs. lol