You isolate an infectious substance that is capable of causing disease in plants,but you do not know whether the infectious agent is a bacterium,virus,or prion.You have four methods at your disposal that you can use to analyze the substance in order to determine the nature of the infectious agent.
I.Treat the substance with nucleases that destroy all nucleic acids and then determine whether it is still infectious.
II.Filter the substance to remove all elements smaller than what can be easily seen under a light microscope.
III.Culture the substance by itself on nutritive medium,away from any plant cells.
IV.Treat the sample with proteases that digest all proteins and then determine whether it is still infectious.
If you already knew that the infectious agent was a prion,which treatment listed above would allow you to distinguish this?
A)I only
B)II only
C)III only
D)either I or IV

Question

Quizplus · Accepted Answer

If the infectious agent is a prion, treating the substance with nucleases (I) would not be effective since prions do not contain nucleic acids. Filtering out small elements (II) or culturing the substance on nutritive medium (III) could still contain prions, so these methods would not allow for a distinction between a prion and other infectious agents. However, treating the sample with proteases (IV) that digest proteins would be effective since prions are composed of protein.

You Isolate an Infectious Substance That Is Capable of Causing