The Immune System

2. Animals that carry disease causing organisms from person to person.
5. A protein that is shaped like the letter Y with two antigen-binding sites.
6. Carbohydrates, proteins, and lipids on the surfaces of viruses, bacteria, and other pathogens that trigger responses by the immune system.
7. _______ are some of the most dangerous pathogens spread from person to person by contact.
16. Uncontrolled cell growth and division.
17. When cancerous cells move about the body.
19. The conclusion that says infectious diseases were caused by microorganisms, or germs.
23. Cancerous tumors.
25. When cells of the immune system are weakened by infection.
27. _______ are compounds that kill bacteria without harming the cells of humans or animals.
29. Noncancerous tumors.
30. Undergoing ______ can cause nausea, hair loss, and headaches.

1. A series of guidelines used to identify the microorganism that causes a specific disease.
3. Disease-causing agent.
4. Smooth muscles contract causing the passageways in the lung to reduce in size.
8. Poisons that produce illness by disrupting bodily functions.
9. A nonspecific reaction to tissue damage caused by injury or infection.
10. A mass of growing tissue.
11. Any change other than an injury that disrupts the normal functions of the body.
12. Defense that attacks disease-causing agents.
13. When the body attacks itself it produces a(n) _______.
14. The immunity produced by a vaccine.
15. The Greek physician Hippocrates noted that people who survived certain diseases had acquired ______.
18. Your body's most important nonspecific defense.
20. Immunity against pathogens in the body fluids.
21. When scientists create a weakened or mild form of a pathogen to produce immunity, they are creating a(n) ________.
22. When allergy causing antigens attach themselves to mast cells, the activated mast cells release chemicals known as ______.
24. Scientists named proteins ______ because they interfere with the virus.
26. Common overreactions of the immune system.
28. Elevated body temperature that slows or stops the growth of pathogens.