What is the function of an antibody?

The function of an antibody is to act against a specific antigen. Antibodies are proteins produced by the immune system in response to foreign substances, known as antigens, which can include pathogens like bacteria and viruses. Each antibody is uniquely shaped to bind to a specific antigen, allowing the immune system to target and neutralize harmful invaders effectively.

When antibodies bind to their respective antigens, they can neutralize pathogens directly by blocking their ability to infect cells, or they can mark them for destruction by other immune cells. This specificity is crucial for the immune response, as it ensures that the body can precisely identify and respond to a wide variety of threats without mistakenly attacking its own cells. The other options reflect different aspects of immune responses or functions of immune cells, but they do not define the primary role of antibodies directly.