As we know, the way that blood moves inside the circulatory system of the developing Fetus is quite different than the way that blood moves inside the circulatory system of the fully functional adult individual. So in this lecture we're going to discuss, we're going to focus on the way that blood moves inside the heart of that developing Fetus. So let's begin inside the inferior venacava. So we know that along the inferevenicaver, we have the partially oxygenated blood that is moving along and eventually moves into the right atrium of the heart. But before it moves into the right atrium of the heart, the partially oxygenated blood that moves along the inferior venecrava eventually combines with the deoxygenated blood that is moving along the superior venecave and which is coming from the extremities found on the upper side of that developing Fetus. So we have the deoxygenated blood is moving along our superior venecaa.