| A | B |
|---|
| immune system | body system that fights off infections |
| phagocyte | cell that destroys other cells by surrounding and engulfing them |
| T cell | white blood cell that matures in the thymus and destroys infected body cells by causing them to burst; also called a T-lymphocyte |
| B cell | white blood cell that matures in the bone marrow and produces antibodies that fight off infection; also called a B-lymphocyte |
| antibody | protein produced by B cells that aids in the destruction of pathogens |
| interferon | type of protein, produced by body cells, that prevents viruses from replicating in infected cells |
| passive immunity | immunity that occurs without the body undergoing an immune response |
| active immunity | immunity that occurs after the body responds to an antigen |
