Immunity produced by exposure to an antigen, resulting from the immune response is called what?

• A. Active immunity
• B. Passive immunity
• C. Innate immunity
• D. Inflammatory response

Answer: (A)

This question is about immunity that develops after your immune system actually encounters an antigen and mounts a response, creating memory for future protection. When exposed to an antigen, B cells become plasma cells that produce specific antibodies and some B and T cells become memory cells. This makes the protection long-lasting and quicker if you meet the same antigen again. That’s why this is called active immunity—it comes from your own immune system responding to the threat, whether through natural infection or vaccination.

In contrast, passive immunity is when you receive antibodies from another source, giving immediate protection but not lasting memory because your own immune system wasn’t activated. Innate immunity refers to non-specific defenses present from birth, like skin barriers and phagocytes, which don’t involve a targeted immune response or memory. The inflammatory response is part of that innate defense system and isn’t a form of lasting immunity.