1. the improper functioning of the body brought about by heredity, infection, diet, or the environment protozoan infection 2. cannot be spread through contact or any mechanism of transmission infectious disease 3. caused by the spread of harmful microorganisms bacterial infection 4. caused by the multiplication of a small infectious agent which invades a host cell and then destroys it non-infectious disease 5. caused by the reproduction of a small infectious agent which produces poisons that destroy cells viral infection 6. caused by the multiplication of fungal organisms on or in the body fungal infection 7. caused by microscopic parasites disease

You isolate an infectious substance capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. you have four methods at your disposal to analyze the substance and determine the nature of the infectious agent.i. treat the substance with enzymes that destroy all nucleic acids and then determine whether the substance is still infectious.ii. microscope.iii. culture the substance on nutritive medium, away from any plant cells.iv. treat the sample with proteases that digest all proteins and then determining whether the substance is still infectious.if you already know that the infectious agent was either bacterial or viral, which method(s) listed above would allow you to distinguish between these two possibilities? a) ib) iic) ii or iiid) iv