Across
- 1. Blood vessels that contain valves to prevent backflow
- 4. A vaccine provides this type of immunity
- 6. The matching relationship between antigen and antibody shapes
- 10. The process by which phagocytes engulf pathogens
- 11. The network of fibres that forms during blood clotting
- 13. The protein in red blood cells that carries oxygen
- 15. A disease that can be spread from person to person
- 17. Blood vessels where exchange of substances occurs
- 20. The movement of materials out of a cell
- 21. Blood vessels that carry blood away from the heart
- 22. The phase of the heartbeat when the chambers contract
Down
- 2. The type of immunity gained after an infection
- 3. A microorganism that causes disease
- 5. The large blood vessel that carries blood from the heart to the body
- 7. Proteins produced by lymphocytes that bind to antigens
- 8. An organelle containing enzymes that digest pathogens
- 9. The liquid component of blood that transports substances
- 10. White blood cells that engulf and digest pathogens
- 12. The movement of materials into a cell
- 14. A cell that remembers a pathogen for faster future response
- 16. The clumping of red blood cells due to incompatible blood
- 18. A substance on the surface of a pathogen that triggers an immune response
- 19. The body’s ability to resist infection