IMMUNOLOGY

Detailed explanation-1: -Once the body produces antibodies in its primary response to an antigen, it also creates antibody-producing memory cells, which remain alive even after the pathogen is defeated by the antibodies.

Detailed explanation-2: -The preventative injection of a non-pathogenic antigen into the organism allows the body to generate a durable immunological memory. The injection of the antigen leads to an antibody response followed by the production of memory B cells.

Detailed explanation-3: -The primary immune response to antigen occurs on the first occasion it is encountered. This response can take up to 14 days to resolve and leads to the generation of memory cells with a high specificity for the inducing antigen.

Detailed explanation-4: -Immunological memory is the ability of the immune system to respond with greater vigor upon re-encounter with the same pathogen and constitutes the basis for vaccination (Ahmed and Gray, 1996).