Your bone marrow, which has a spongy consistency, fills the cavities inside your bones and produces blood cells. Healthy bone marrow constantly supports your bone renewal and produces red blood ...

Red blood cells are disc-shaped cells with no nucleus. They are very small but their flattened shape gives a relatively large surface area which allows rapid diffusion of oxygen.

Red blood cells carry oxygen from the lungs to every other organ, and blood-forming stem cells must make about 200 billion new red blood cells each day to keep the oxygen flowing.