And now our de oxygenated blood can flow via the pulmonary arteries and into the left and the right lung. Now, at the same exact moment in time we have our filling of this left ventricle. Because it is now fully filled with oxygenated blood. It causes contraction of the left ventricle closing this valve known as the mitral or the bicuspid valve. At the same time, it forces the opening of the aortic valve and it forces the movement of our oxygenated blood into the aorter of our body. And that aorta basically diverges into many smaller arteries and that moves our oxygenated blood into the rest of our body.