Class 11 NEET Biology Body Fluids and Circulation

(d) : WBCs are the colourless nucleated amoeboid cells that can squeeze through blood capillaries by a process known as diapedesis. The increase in their number causes leukaemia, a cancer. WBCs are of two types, granulocytes (formed in bone marrow) and a granulocytes (formed in bone marrow and thymus).