Erythropoiesis is the process by which new red blood cells, or erythrocytes, are produced in the body. This process primarily occurs in the bone marrow and is essential for maintaining adequate oxygen levels in the blood. The production of red blood cells is stimulated by a hormone called erythropoietin, which is released by the kidneys in response to low oxygen levels. During erythropoiesis, stem cells in the bone marrow differentiate into various stages of red blood cell precursors. These precursors undergo several changes, including the loss of their nucleus, to become mature red blood cells. Once fully developed, these cells enter the bloodstream, where they transport oxygen from the lungs to tissues throughout the body.