Well, recall that oxygen always spontaneously and naturally travels from a high concentration of oxygen to a low concentration of oxygen, from a high partial pressure of oxygen to a low partial pressure of oxygen. And we'll see that's exactly what happens when the hemoglobin actually reaches the tissues and organs of our body. Now, by the way, the way that we designate partial pressure of oxygen is p two, where P is the partial pressure and two is our oxygen. So we know what happens to our oxygen when the alveoli basically released that oxygen into the capillaries. But what happens to our oxygen as the hemoglobin and the red blood cells carry that oxygen along our blood vessel system, to our tissues and organs of the body? So as hemoglobin carries oxygen in the red blood cells and within our blood plasma of the blood vessels, it protects the non polar water molecule from the polar cytoplasm of the red blood cell and the polar plasma of our blood.