Function and classification of white blood cells
WHITE BLOOD CELLS WBC LEUCOCYTES
White blood cells are the cells of the immune system that are involved in protecting the body . Some leucocytes migrate into the tissues of the body to take up a permanent residence at that location rather than remaining in the blood
White blood cell are generally colourless , larger in size as compared to Red Blood Cell. There is nucleus generally having two or more lobes.
White blood cell are made inside the bone marrow ,some white blood cell have a lifespan of one to three days, so bone marrow is constantly making them. The wbc is less when compared to RBCs about 8000 cu.mm of blood .
The formation of white blood cell or synthesis of white blood cell , in bone marrow located in bones of adult.
CLASSIFICATION OF White Blood Cells
WBC are classified as:-
In the cells cytoplasm there is a presence of granules.
Granulocytes are of three types:-
Neutrophils are called polymorphs or polymorphonuclear cells because their nucleus form more lobes they are type of granulocytes , there granules are fine and uniformly distributed .They kill and digest bacteria and fungi ,
Eosinophils are type of granulocytes, they are also called ACIDOPHILS because they are mainly stained by acidic dyes.These are cells that are slightly larger then neutrophil. There granules are rough , large and closely packed and nucleus are SPECTACLE BILOBED SHAPE . Normal eosinophil count is 2-4% of blood WBCs. They attack and kill parasites , destroy cancer cell.
Basophil are called Bisophil because they are stained by blue basic dyes and their nucleus is kidney shaped. These are generally called MAST CELL , as they contain heparin, histamine . Normally basophil count is 0.5% of total WBC . They have two lobes.
Agranulocytes is type of WBCs where granules is absent,here cytoplasm is clean. They have single nucleus which is not lobed.
Agranulocyte is further divided into two types:-
Lymphocyte create antibodies to defend against bacteria , viruses.They contain 25%of total WBCs , and their nucleus size is size of cell , which means they occupy almost area of cells , it is their criteria .
They are of two types:-
- SMALL LYMPHOCYTE
- LARGE LYMPHOCYTE
Monocyte are the largest of WBCs .They have a longer lifespan than many WBCs and help to break down bacteria . They contain 2-4% of WBCs and also contains eccentric nucleus.
FUNCTION OF WHITE BLOOD CELL
- Protection from infection (destruction effective organs.) This is done by neutrophil and monocytes which engulf bacteria . This process is called an PHAGOCYTOSIS.
- To help in tissue repair mechanism , so that new cell can form.
- To produce immune substances which defend against disease i.e. antibodies .This is done by lymphocyte through the synthesis of γ-globin( γ -globulin).
- Basophil produce an anti – clotting substance called HEPARIN.