Pathogens

6. blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances which the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.
8. a microscopic organism, especially a bacterium, virus, or fungus.
10. a small animal with a long thin body, no bones and no legs.
11. contagious bacterial disease characterized by fever and delirium, typically with the formation of buboes ( bubonic plague ) and sometimes infection of the lungs ( pneumonic plague
14. The invasion and growth of germs in the body
15. a very simple microorganism that infects cells and may cause disease.

1. A large group of single-cell microorganisms.
2. one-celled animals found worldwide in most habitats
3. organism that lives in or on an organism of another species (its host) and benefits by deriving nutrients at the other's expense.
4. substances created by plants and animals that are poisonous (toxic) to humans
5. agents that are transmissible and are able to induce abnormal folding of specific normal cellular proteins called prion proteins that are found most abundantly in the brain.
7. disorder of structure or function in a human, animal, or plant, especially one that has a known cause and a distinctive group of symptoms, signs, or anatomical changes
9. the state or quality of being resistant to a particular infectious disease or pathogen.
12. widespread occurrence of an infectious disease in a community at a particular time.
13. plant-like organism that does not make chlorophyll.