And what that causes is these two semi lunar valves, our pulmonary semi lunar valve and our aortic semilunar valve, to basically open up. And as those valves open up, all that blood flows from the ventricles into our arteries. So the left ventricle sends that oxygenated blood into the order, while the right ventricle sends our deoxynated blood into the pulmonary arteries and eventually into our lungs. So within the st segment, all of the cells within the ventricles have been depolarized, and repolarization of those cells basically begin. Now, the semi lunar valves, both of them, actually open up and our blood begins to eject into these blood vessels. This takes place in this flat region, the st segment, where the voltage is basically flat.