So because on the right side of the heart we have a higher pressure then on the left side of the heart, as a result of the high pressure inside the lungs, the majority of that blood, the partially oxygenated blood, will move from the right atrium, this chamber here, via the pharamino valley and into the left atrium of the heart. Now, what exactly is this for amino valley? Well, in that developing Fetus, the wall that is separating the two atria contains this one way door, a valve system. And if we push against that valve system, it essentially opens up. And so because of the higher pressure, it pushes against this forraminal valley, the valve, and it basically pops open and the blood flows into the left atrium of the heart. And as a result, what that means is the partially oxygenated blood is able to actually bypass those nonfunctional high pressure lungs.