What type of immunity involves the secretion of antibodies?

What type of immunity involves the secretion of antibodies?

• A. Cell-mediated immunity
• B. Humoral immunity
• C. Adaptive immunity
• D. Innate immunity

Answer: (B)

Humoral immunity is a specific type of adaptive immunity that involves the secretion of antibodies by B lymphocytes, or B cells. When B cells encounter an antigen that matches their specific receptors, they undergo activation and differentiation. This process leads to the proliferation of plasma cells, which are the effector form of B cells responsible for producing antibodies. These antibodies are then released into the bloodstream, where they bind to antigens, neutralizing them or marking them for destruction by other components of the immune system.

This type of immunity is particularly effective against extracellular pathogens such as bacteria and viruses found outside of cells, allowing the body to effectively target and eliminate these threats. The antibodies produced during humoral immunity can also provide long-lasting protection through memory B cells, which enable a quicker and more efficient response upon re-exposure to the same pathogen.

In contrast, cell-mediated immunity involves T lymphocytes and does not primarily rely on antibodies. Rather, it deals with the destruction of infected cells and the regulation of immune responses. Adaptive immunity encompasses both humoral and cell-mediated immunity, but the specific action of antibody secretion directly aligns with humoral immunity. Innate immunity refers to the body's first line of defense, which includes barriers and general immune responses that do not involve memory or