What term refers to molecules that activate adaptive immunity?

• A. Antibodies
• B. Antigens
• C. Immunogens
• D. Epitopes

Answer: (C)

Immunogens are molecules capable of provoking an adaptive immune response. They’re recognized as foreign and can be processed to activate B cells and T cells, leading to antibody production and the development of immune memory. Within an immunogen, specific regions called epitopes are the exact parts that receptors on B cells or T cells bind to. While antigens are any substances that the immune system can recognize, not every antigen will necessarily trigger a response on its own—some are weakly immunogenic or require a carrier protein to become effectively immunogenic. Antibodies are the products of the immune response to immunogens, acting as the soluble effectors that bind to the immunogen.