Across
- 1. – Invertebrate blood cells
- 3. – Disease protection
- 5. – Animals with backbones
- 8. – Inborn defense
- 12. – Learned response
- 13. – Grainy white blood cells
- 15. – Disease-causing agents
- 16. – Infection-related
Down
- 2. – Mouth fluid
- 4. – Antiviral proteins
- 6. – Allergy-related cells
- 7. – Engulfing immune cells
- 9. – First-responder white cells
- 10. – Sticky body secretion
- 11. – Insect blood fluid
- 14. – Branching cell extensions