ISM / SCIENCE PHOTO LIBRARY ISM / SCIENCE PHOTO LIBRARY
Maturing white blood cells. Coloured transmission electron micrograph (TEM) of immature white blood cells (leucocytes) in a bone marrow biopsy. These precursor cells are called myeloblasts (right) and promyelocytes (left). The myeloblasts can develop into any of four types of white blood cell: basophils, neutrophils and eosinophils (all known as granulocytes), and monocytes. Promyelocytes are descended from myeloblasts. The myeloblasts are called promyelocytes when they have become more developed and too specialised to develop into monocytes. The monocyte equivalent to promyelocytes are called monoblasts. White blood cells are made in the bone marrow constantly, as their lifespan is very short. Magnification: x5555 when printed 10 centimetres wide.
Model release not required. Property release not required.