( A ) Leucocytes are generally short lived and are relatively lesser in number which averages 6000-8000 mmñ3 of blood.
( B ) Leucocytes are colourless due to the lack of haemoglobin and they are nucleated
( C ) Neutrophils and lymphocytes (6-8 per cent) are phagocytic cells which destroy foreign organisms entering the body.
( D ) Two main categories of WBCs are granulocytes and agranulocytes.
