Acquired immunity

 Acquired immunity 

Producing specific cells and molecules which are directed against the foreign invaders. It has the special ability to keep memory of first time exposure of an antigen (primary immune response) and mounts better response when there is second time exposure of same antigen (secondary immune response). This ability of immune response forms the basis for the immunization or vaccination.

 

Acquired immunity is classified into humoral immunity and cell mediated immunity. Both humoral and cellular immune responses are evoked during antigen exposure.

 

The acquired immunity can be either active or passive.

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