Question

You have a series of rII mutants but only limited information about them. You have information about every single mutant for the following tests. In test 1, each single mutant is grown on E. coli B, creating a lysate that has a massive number of phage in it. These phage are tittered (tested for infectivity) on E. coli B (to determine total number of particles) and on E. coli K, which can tell us what? (2 points)

A. Plating on K will tell us nothing.

B. Plating on K will tell us something but we need more information.

C. Nothing, because rII mutants are unable to productively infect E. coli K.

D. The number of plaques observed on E. coli K relative to E. coli B will tell us the reversion/suppression rate for an individual rII mutant.

E. The number of plaques observed on E. coli K relative to E. coli B will tell us the recombination rate for an individual rII mutant.

Answer 1

B. Plating on K will tell us something but we need more information.

Plating K might give a hing about reversion/suppresion rates, but it will not be enough to obtain significant information about the rII mutants.