Immune System

1. A protein produced by B cells that specifically binds to an antigen to neutralize or mark it for destruction.
4. A network of vessels and organs that circulate lymph and support immunity.
7. A microorganism that causes disease, such as bacteria, viruses, fungi, or parasites.
8. Cells of the immune system that defend the body against infectious disease and foreign invaders.
10. A type of white blood cell that performs phagocytosis and presents antigens to T cells.
13. Long-lived B or T cells that respond quickly upon re-exposure to a pathogen.
14. A preparation containing antigens that stimulate immunity without causing disease.

2. The process of making someone immune, usually through vaccination.
3. Barrier, Beneficial microbes that compete with pathogens and prevent infection.
5. A response to infection or injury marked by redness, heat, swelling, and pain.
6. Barrier, Structures like skin and mucous membranes that block pathogen entry.
9. An increase in body temperature that helps inhibit pathogens and boost immune activity.
11. Barrier, Substances like stomach acid and enzymes that destroy or inhibit pathogens.
12. An exaggerated immune response to harmless substances like pollen or dust.