In healthy red blood cells (RBCs), myosin fibers (blue) contract, pulling on actin (pink) and spectrin proteins (purple) connected to the cell membrane and helping to give the cells their distinct, ...

Healthy fresh red blood cells have a distinctive biconcave—or dumbbell—shape for efficient oxygen release. During refrigerated storage, red cells become energetically stressed and more spherical, ...

Red blood cells transport oxygen throughout your body, including to vital organs and tissues. They also help your body get rid of carbon dioxide. Too little or too many red blood cells may be ...

Human bodies make 2 million red blood cells per second. They each live for 120 days and spend that time zooming completely around the body every 20 seconds, carrying oxygen from the lungs to other ...