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