this is the joke about fractions. they are useless.
they are only used in medicines. If you bleeding out your red/white blood cells are low or platelets you NEED at least a component transfusion.
Hemoglobin is the only ingredient of red blood cells. The only difference between hemoglobin and a red blood cell is the sack that holds the hemoglobin together. Its made of cholesterol.
once its out of the sack its no good for transfusion.