False-colour scanning electron micrograph of white blood cells from a patient with chronic myeloid leukaemia (CML). The leukaemic cells show ridge-like profiles and ruffles across their surfaces. The micrograph also shows a scattering of red blood cells. Leukaemia is a malignant disease in which the bone marrow and other blood- forming organs overproduce certain types of white blood cells. These immature and abnormal cells suppress the normal production of white and red cells, thereby increasing the susceptibility to other infections such as anaemia. Magnification: x2573 at 35mm size.