CHAPTER 19: THE CARDIOVASCULAR SYSTEM: THE BLOOD

RBC Life Cycle Red blood cells only live about 120 days because of the wear and tear on their plasma membranes as they squeeze through blood capillaries. In the RBC life cycle, after phagocytosis of worn-out RBCs by macrophages, hemoglobin is recycled (Figure 19.5); the globin portion is split from the heme with the amino acids being reused for ... ................
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