Introduction: Hematopoiesis is an on going process mammalian marrow system. A few cells from the nucleated cells of bone marrow are hematopoietic cells which include primary stem cells, precursor cells and progenitor cells. Primary stem cells and progenitor cells are able to produce colonies in culture medium (CFU-C) and irradiated mouse spleen (CFU-S). A hematopoietic cell is alive and act...