Final answer:
Antibodies react with specific chemical targets called antigens. Antigens are molecules that stimulate an immune response in the body. When antibodies attach to antigens on pathogens, they can initiate the destruction of the pathogen by other immune cells.
Step-by-step explanation:
An antibody is a molecule that specifically binds to and reacts with a specific antigen. Antigens are molecules, usually proteins, that stimulate an immune response in the body. When antibodies attach to antigens on the surface of pathogens (such as bacteria or viruses), they can initiate the destruction of the pathogen by other immune cells.