Define White Blood Corpuscles as Internal Defence Mechanism

The white blood cells are probably the most important part of our immune system. You may recall reading about the white blood cells in the last unit. We learnt that, whenever a germ or infection enters our body, the WBCs snap to attention and destroy the culprit. During an infection, the number of leukocytes increases. The total leukocyte count is about 4000- 11 000 per cubic mm of blood. Of these, 50 to 70 % are neutrophils, 20-40% are lymphocytes, 2-8% are monocytes, 1-4% eosinophils and 0-1% basophils. WBCs creep out of the capillaries by amoeboid movement into the intercellular spaces if there is an infection. This process is called diapedesis.