Do section 31.1 and answer questions 1-5, Section 31.2 questions 1-5, Section 31.3 Questions 1-5 and section 31.6 questions 1-4. 31.1 1.The pathogen must be present in every case in which the disease is found. It must be isolated and grown outside the body in pure culture. Healthy animals infected with culture must develop the disease and then the pathogen must be re-isolated and cultured from the newly sick animals and must be identical to the original pathogen. 2.The five main types: viruses, bacteria, fungi, protozoa, and parasites. 3.Pathogens can be spread through skin contact, bodily fluids, airborne particles, contact with feces, and touching a surface that was touched by an infected person. 4.Bacteria destroy healthy cells and release chemicals or toxins. Viruses take over and make it produce more of the virus and inject DNA. 5.Lister began using a weak acid to clean his operating tools and his patients’ wounds before surgery and this decreased the number of deaths in his patients dramatically.
