Across
- 4. different people have different levels of ___ to certain diseases?
- 5. immune systems go after some time, so what do we need?
- 7. what do vaccines introdusc that are already killed or modified so we don't get sick?
- 8. the immune system develops all kinds of ___ that help destroy diseases causing microbes?
Down
- 1. what has cells that perform specific functions?
- 2. active immunity and ___immunity are the two ways our body can gain immunity?
- 3. what do scientists call invaders that can cause diseases?
- 6. it is possible to get antibodies from animals or people through _____?