hematopoiesi
Hematopoiesis is the process by which the body's blood cells are produced. In humans, it begins during embryonic development and continues for life, with the bone marrow serving as the principal site of production in postnatal individuals. Primitive hematopoiesis occurs in the yolk sac, providing early erythroid cells, while definitive hematopoiesis arises in the fetal liver and later the spleen before the bone marrow becomes the dominant site around birth. After infancy, hematopoiesis is maintained primarily in the bone marrow, although under certain conditions, such as stress or disease, extramedullary sites like the liver or spleen can resume activity.
Hematopoietic stem cells (HSCs) reside in specialized bone marrow niches and give rise to all blood cell
Dysregulation of hematopoiesis can lead to anemia, leukemias, and other marrow disorders. Assessment often involves blood