An introduction to hemoglobin physiology.

Hemoglobin plays an important physiologic role, one that begins early in fetal development. The focus of this article is hemoglobin physiology. Developmental erythropoiesis, developmental stages of hemoglobin, and postnatal erythropoiesis and hemoglobin production are discussed. The function of hemoglobin, its affinity for oxygen, and the clinical significance of the oxyhemoglobin dissociation curve are also explored.