Across
- 3. The simplest and smallest forms of life
- 4. The practice of keeping yourself and environment clean
- 5. The system in your body that produces substances to help it fight against infection and disease
Down
- 1. A medical condition that causes you to react badly or feel ill/sick when you eat or touch a particular substance
- 2. The appearance of a particular disease in a large number of people at the same time