 And the oxygen attaches to the hemoglobin. There's millions of these in a red blood cell, and there's millions of red blood cells in a milliliter of blood. Anyways, lots of them. Zillions and zillions and zillions of these things. Anyways, they go and they carry the oxygen over to the parts of your body that need it. The oxygen jumps off the hemoglobin and goes into your cell, except for it doesn't jump off the hemoglobin.