. Basic concepts of immunology Immunology is the study of immune system. This system protects an indvidual from various infective agents. It refers to all the mechanisms used by the body for protection from environmental agents that are foreign to the body.
When the immune system does not function efficiently in an individual, it leads to infection causing disease. The overall ability of body to fight against the disease causing pathogen is called immunity . It is also called disease resistance and the lack of immunity is known as susceptibility. Immunity is highly specific.
Normally many of the responses of the immune system initiate the destruction and elimination of invading organisms and any toxic molecules produced by them. These immune reactions are destructive in nature and are made in response only to molecules UNIT - III