IMMUNOLOGY

4. A sticky secretion that traps pathogens at mucosal surfaces.
8. A type of cytokine that directs cell movement.
10. A fluid secreted in the lungs that reduces surface tension and can neutralize pathogens.
13. A general term for agents that kill or inhibit microorganisms.
15. A large phagocytic cell that engulfs pathogens and dead cells.
16. The invasion and multiplication of microorganisms in body tissues.
17. The site where T cells mature.
20. The branch of immunity that is specific and has memory.
21. Small antimicrobial peptides found in epithelial cells.
23. A secretion from glands that contributes to the skin’s chemical barrier.
27. Relating to infections caused by viruses.
28. Signaling proteins released by cells to mediate and regulate immunity.
29. A microorganism that causes disease.
30. The largest organ and a key physical defense against infection.

1. A major component of bacterial cell walls, recognized by innate immune receptors.
2. A localized response to injury or infection, involving redness, swelling, and heat.
3. An immune cell that releases histamine during allergic responses.
5. A small structure that filters lymph and supports immune cell activation.
6. The process by which cells engulf and digest microbes and debris.
7. Any substance that is recognized as foreign by the immune system.
9. An organ involved in filtering blood and immune surveillance.
11. A group of proteins that enhance immune responses by lysing pathogens or marking them for destruction.
12. A protein produced by B cells that binds to a specific antigen.
14. An enzyme in secretions that breaks down bacterial cell walls.
18. The process of blood cell formation in the bone marrow.
19. The immune-rich area of the spleen involved in pathogen detection.
22. Short-lived phagocytic cells that are first responders during infection.
24. A physical or chemical structure that prevents pathogen entry.
25. Immune cells including B cells and T cells.
26. Type of immune response that leads to a faster reaction upon re-exposure.