Red blood cell evolved a mode of red blood cell development substantially different from the mammalian norm. Overall, mammalian red blood cells are remarkably flexible and deformable so as to squeeze through tiny capillaries, as well as to maximize their apposing surface by assuming a cigar shape, where they efficiently release their oxygen load. Red blood cells in mammals are unique amongst vertebrates as they do not have nuclei when mature. Red blood cells of mammals cells have nuclei during early phases of erythropoiesis, but extrude them during development as they mature; this provides more space for hemoglobin. The red blood cells without
Blood doping or storage is another issue. Contamination was seen in 1 in every 500,000 transfusions of red blood cells in 2002. Blood contamination can lead to septicemia or an infection that affects the whole body. Certain medications used to increase red blood cells can reduce liver function and lead to liver failure, pituitary problems, and increases in cholesterol levels. Blood doping Blood doping is the practice of boosting the number of red blood cells in the bloodstream in order to enhance athletic performance. Because such blood cells carry oxygen from the lungs to the muscles, a higher concentration in the blood