Across
- 2. poisonous or not pure
- 9. two things are different but together form a useful combination
- 10. the entry of a pathogen into the body of a host
- 11. a chemical that damage cells
- 12. the movement of a pathogen from one host to another
- 13. people keep themselves or their environment clean to prevent diseases
Down
- 1. a microorganism that causes disease
- 3. feature that you experience when you have a disease
- 4. to know someone or something because you have seen or experienced it before
- 5. a dead or weakened pathogen that is injected into the body to induce an immune response
- 6. a chemical that is recognised by the body as being"foreign"
- 7. an organism in which a pathogen lives and reproduces
- 8. a protein with a particular shape which helps to kill pathogens