white blood cells which are divided into two main categories: granular and non-granular.
1) Granulocytes - Leukocytes characterised by the presence of differently staining granules in their cytoplasm when viewed under light microscopy. These include
i) Neutrophils - They have a multilobed nucleus. Neutrophils make up 65% of the body's white blood cells and are the most numerous. Because they are phagocytic they are mainly found at the sites of wounds. They engulf any bacteria that try to get into the body through the site of the wound
ii) Eosinophils make up anywhere from 2-4% of of the body's white blood cells and are mainly responsible for attacking parasites that enter the blood stream. They usually have bilobed nucleus.
iii) Basophils - They make up 0.5% of the body's white blood cells and are responsible for the production and secretion of antibodies
2) Agranulocytes - leukocytes characterized by the apparent absence of granules in their cytoplasm. These include
i) Lymphocytes - These make up 20-25% of the body's white blood cells and are responsible for helping the body to develop immunity towards infections. Lymphocytes also produces antibodies which are designed specifically to target the excretions of harmful bacteria. They will also help the Neutrophils do their job by clustering the bacterium together so that they can be engulfed by the phagocytes easily.
ii) Monocytes - They make up 3-8% of the body's white blood cells and they take on the bacteria that the Neutrophils are unable to handle. Monocytes are also phagocytic