The blood cells are of three major types they are erythrocytes(RBC), leucocytes(WBC) and platelets. Two main categories of WBCs are granulocytes and agranulocytes. Neutrophils, eosinophils, and basophils are different types of granulocytes, while lymphocytes and monocytes are the agranulocytes. Lymphocytes are of two major types – ‘B’ and ‘T’ forms. Both B and T lymphocytes are responsible for immune responses of the body.B lymphocytes are responsible for humoral immunity and T lymphocytes in cell-mediated immunity. Hence lymphocytes are not phagocytic.