White blood cell Types of white blood cells Granulocytes Basophils
 Basophils are rare granulocytes. If you had 1000 white blood cells, only 1 to 3 of them would be Basophils. Theit nucleus is hidden by granules which turn dark blue in color when stained. Basophils carry histamine and heparin, and other protein chemicals. They appear at the sites of ectoparasite infection, or allergies. We don't know exactly how they work.