define immunity,immunisation and vaccine .

Immunity is the ability of our body to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells.

 

Immunisation is the process by which immunity to infectious diseases is produced artificially by introducing specific antigens (dead or weakened microorganisms) into the body. The body produces antibodies in response to the antigens, giving protection from that disease.

 

Vaccine is a biological preparation consisting of a suspension of weakened or dead pathogenic cells injected in the body in order to stimulate the production of antibodies.