The blood is made up of red blood cells, white blood cells, and platelets.
All of these parts of the blood are moved by plasma, which is a yellow liquid in the blood, it takes up 55% of it.
Red blood cells are like dump trucks that bring oxygen to the heart from the lungs and take the waste products away. They take up 44.5% of all of your blood.
The other 0.5% of the blood are white blood cells and platelets. White blood cells are like the police of your blood. They locate any germs, surround them, and kill them.
Platelets are like the highway repair team. Their job is to cover any cuts with fibrin webs that turn into scabs, so that blood does not get out and germs do not come in.
When a blood cell becomes old it becomes stiff and then is broken down by the liver or spleen. After it is broken down, the iron and hemoglobin salvaged from it is sent to the marrow where more blood cells are produced. sw