Question

35) Refer to the treatments listed to answer the question. You isolate an infectious substance capable of causing discase in plants, but you do not know whether the infectious agent is a bacterium, virus, or prion. You have four methods at your disposa 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. Filter the substance to remove all elements smaller than what can 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 determine whether the substance be easily seen under a light is still infectious. If you already know that the infectious agent was either bacterial above would allow you to distinguish between these two possibilities? or viral, which method(s) listed A) I B) 11 C) II or III D) IV

Answer 1

35. II or III

36. A) and D)

9. A)

1. D) I, II and III - all three structure contain nucleic acid enclosed in a protein coat.