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hematopoiesis he·ma·to·poi·e·sis (hē'mə-tō-poi-ē'sĭs, hĭ-māt'ə-) or he·mo·poi·e·sis (hē'mə-)
The formation of blood or blood cells in the living body. Also called hematogenesis, sanguification.
continuous process by which the cellular constituents of blood are replenished as needed. Blood cells are divided into three groups: the red blood cells (erythrocytes), the white blood cells (leukocytes), and the blood platelets (thrombocytes). The white blood cells are subdivided into three broad groups: granulocytes, lymphocytes, and monocytes.