Question

Explain the role of histamine, interferon, B cells in providing defence against infection in our body.

Answer 1

Histamine is produce by mast cells and the basophils in the connective tissues of the body. The function of the histamine is to enhance permeability of the capillaries to white blood and other immune proteins to be available to fight pathogens in infected sites. 

Interferon are molecules that are used for inter-cell communication. The interferon are produced by cells in response to infection by pathogens such as bacteria, viruses and fungi. They act as messengers to the adjacent cells, to prepare their immune defense system for the particular infection present.

B cells are types of white blood cells. Their function is to secrete antibodies which are useful in the process of opsonization of invading pathogens. The B cells also secrete cytokines and they are themselves antigen-presenting cells. 

Answer 2

Histamine act as a messenger travelling to the site of irritation to activate a certain resposce.it binds with special receptors in the protein molecule.it causes several important effect at the site of infection like dilating or widening small blood vessels of that area hence increasing the blood flow leading to inflammation.

Interferon stops the replication of many viruses,hence stopping there growth.

B cells are lymphocytes which produces antibodies which attack the bacteria and toxins.