Leukaemia. False-colour scanning electron microgr- aph of white blood cells from a patient with acute lymphoblastic leukaemia (ALL). 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: x980 at 35mm size, x2400 at 6x6cm size.