Haematopoiesis

Haematopoiesis (from Ancient Greek: αἷμα, "blood"; ποιεῖν "to make") (or hematopoiesis in American English; sometimes also haemopoiesis or hemopoiesis) is the formation of blood cellular components. All cellular blood components are derived from haematopoietic stem cells. In a healthy adult person, approximately 1011–1012 new blood cells are produced daily in order to maintain steady state levels in the peripheral circulation.