Final answer:
A single antigen can have multiple epitopes, and different antibodies can bind to different epitopes on the same antigen. Haptens become antigenic by attaching to a larger carrier molecule.
Step-by-step explanation:
A single antigen molecule may be composed of many individual epitopes. Epitopes are the smaller exposed regions on the surface of antigens that antibodies recognize and interact with. A single antigen can have multiple epitopes, and different antibodies can bind to different epitopes on the same antigen. Haptens, on the other hand, are small molecules that are not antigenic by themselves. They become antigenic by attaching to a larger carrier molecule, typically a protein, to produce a conjugate antigen