And this one is also known by the name of the mitral valve or the bicuspid valve. Now what exactly is the point of the left atrial ventricular valve? This is valve number three. So when our left ventricle is relaxed, blood flows from the left atrium into the left ventricle. And to make sure this blood flows, this valve number three must be open. But when our left ventricle contracts, valve number three closes to prevent the backflow, the movement of blood back into the left atrium.