6. Acquired immune (adaptive/specific) responses can be active or passive. Describe and differentiate the two.
Both are types of acquired immunity..
Active immunity is so named because the host plays an active role in responding to the foreign antigen. The best example of active immunity is immunization, whereby a vaccine containing a foreign antigen is administered to a nonimmune host, resulting in active production of specific antibody and lymphocyte-based memory.
Passive immunity refers to transfer of soluble factors (either antibodies or cells) from an immune individual to a nonimmune host. This process confers immunity passively, without the recipient needing prior exposure to the antigen. A good example of passive immunity is parenteral administration of immune serum globulin to travelers as preexposure prophylaxis against unusual infections.
