Although one type of leukocyte called memory cells can survive for years, most erythrocytes, leukocytes, and platelets normally live only a few hours to a few weeks. Thus, the body must form new blood...Although one type of leukocyte called memory cells can survive for years, most erythrocytes, leukocytes, and platelets normally live only a few hours to a few weeks. Thus, the body must form new blood cells and platelets quickly and continuously. Your body typically replaces the donated plasma within 24 hours and it takes about 4 to 6 weeks to replace the blood cells. The process by which this replacement occurs is called hemopoiesis, or hematopoiesis.
