The Immune System
Across
- 3. a B-cell or T-cell that has never been bound to anything is called this
- 4. a chemical barrier
- 7. swelling at the site of an injury is called
- 9. this substance is secreted by mast cells
- 11. communicates with our defense cells, tells them to keep reproducing
- 14. where T-cells mature
Down
- 1. a natural barrier
- 2. the medical term for white blood cells
- 5. the immune system has two parts
- 6. causes the immune system to react abnormally
- 8. the molecules found on the surface of pathogens
- 10. where B-cells are made
- 12. a common name for a bacteria or virus
- 13. a bacteria, virus or other microorganism that can cause disease