Question

Why do the atria contract before the ventricles do? STUDY PICTURES TOO AND IONS LIKE Na ions etc.

Answer 1

SA node (sinoatrial node) – known as the heart's natural pacemaker The impulse begins in a little heap of particular cells situated in the right atrium, called the SA node. The electrical movement spreads through the dividers of the atria and makes them contract. This powers blood into the ventricles. The SA node sets the rate and rhythm of your heartbeat. Ordinary heart rhythm is frequently called typical sinus rhythm on the grounds that the SA (sinus) node fires routinely.

AV node (atrioventricular node) The AV node is a group of cells in the focal point of the heart between the atria and ventricles and acts like a door that moderates the electrical signal before it enters the ventricles. This defers gives the atria time to contract before the ventricles do.