(cells with - lobes of nucleus connected with delicate threads) cells which constitute about %- % of the total WBCs. They are phagocytic in nature and appear in large numbers in and around the infected tissues. Eosinophils have distinctly bilobed nucleus and the lobes are joined by thin strands. They are non-phagocytic and constitute about - % of the total WBCs.
Eosinophils increase during certain types of parasitic infections and allergic reactions. Basophils are less numerous than any other type of WBCs constituting . %- . % of the total number of leucocytes.
The cytoplasmic granules are large sized, but fewer than eosinophils. Nucleus is Figure . Different Types of WBC 0RQRF\WHV 6RPH EHFRPH 0DFURSKDJHV WLVVXHV /\PSKRF\WHV 6RPH EHFRPH 3ODVPDFHOOV (RVLQRSKLOV %DVRSKLOV 1HXWURSKLOV Agranular leucocytes Granular leucocytes XI Std Biology-Zoology Chapter- Monocytes (Macrophages) are phagocytic cells that are similar to mast cells and have kidney shaped nucleus. They constitute - % of the total WBCs.
The macrophages of the central nervous system are the ‘microglia’, in the sinusoids of the liver they are called ‘Kupffer cells’ and in the pulmonary region they are the ‘alveolar macrophages’ . Platelets Platelets are also called thrombocytes that are produced from megakaryocytes (special cells in bone marrow) and lack nuclei. Blood normally contains , , - , , platelets mm of blood. They secrete substances involved in coagulation or clotting of blood.
The reduction in platelet number can lead to clotting disorders that result in excessive loss of blood from the body. . . Blood Groups Commonly two types of blood groupings are done.
They are ABO and Rh which are widely used all over the world. ABO Blood Grouping Depending on the presence or absence of surface antigens on the RBCs, blood group in individual belongs to four different types namely, A, B, AB and O. The plasma of A, B and O individuals have natural antibodies (agglutinins) in them. Surface antigens are called agglutinogens .
The antibodies (agglutinin) acting on agglutinogen A is called anti A and the agglutinin acting on agglutinogen B is called anti B. Agglutinogens are absent in