An infectious substance capable of causing disease in plants is isolated and researchers want to determine whether the substance is a bacterium or a virus. Which of the following methods will best allow them to determine the type of infectious agent they have isolated?
A) Treat the substance with enzymes that destroy all nucleic acids, and then determine whether the substance is still infectious.
B) Culture the substance with plant cells, and then determine whether the cells lyse.
C) Treat the sample with proteases that digest all proteins, and then determine whether the substance is still infectious.
D) Culture the substance on nutritive medium, away from any plant cells.

Question

Quizplus · Accepted Answer

Culturing the substance on a nutritive medium away from any plant cells can help distinguish between bacteria and viruses because bacteria can grow on nutritive media independently, while viruses require a host cell to replicate. If the substance grows on the medium, it is likely a bacterium; if not, it may be a virus.

An Infectious Substance Capable of Causing Disease in Plants Is