| A | B |
|---|
| pathogen | any agent that causes disease |
| white blood cell | blood cell that protects the body against disease |
| antigen | signal molecule that produces an immune response |
| antibody | molecule the body makes to protect itself from disease |
| immunity | resistance to a specific disease |
| contagious | can spread from one person to another |
| antibiotic | chemical made by a living organism that kills bacteria |
| AIDS | viral disease that attacks a person's immune system |
| tumor | mass or lump of cells |
| benign tumor | mass of cells that is usually harmless |
| malignant | harmful mass of cells that can be spread throughout the body |
