Adaptive Immunity

2. A fully differentiated B cell that produces a single type of antibody. (6)
4. A process that diversifies B-cell receptors to bind to new antigens; _______ hypermutation. (7)
6. Term for the five main classes of antibodies (e.g., IgG, IgA). (7)
7. A type of T-cell (CD4+) that assists other white blood cells in immunologic processes. (6)
9. Unresponsiveness of the adaptive immune system to self-antigens. (9)
10. Pertaining to the theory that specific antigen exposure leads to the expansion of a single B or T cell. (6)
11. Immunity mediated by macromolecules found in extracellular fluids, such as antibodies. (7)
13. A protein on a cell surface that binds to a specific molecule. (8)

1. The mechanism by which antibodies block the sites on viruses that they use to enter their target cell. (14)
3. The part of an antigen molecule to which an antibody attaches itself. (7)
5. The unique ability of the adaptive immune system to target specific pathogens. (11)
8. A form of T-cell maturation in the thymus; e.g., positive or negative ______. (9)
12. The strength of the binding interaction between a single antibody binding site and its epitope. (8)