Viruses are isolated from wild typeE.coli cells that have been infected with wild type $\lambda$.These viruses are used to infect a gal^- strain of E.coli. A few bacterial colonies that grow on minimal galactose are obtained while no bacteria are obtained in cells that are not infected.What has happened? A)A $\lambda$ gal⁺ phage was generated B)Reversion mutations have occured. C)The bacteria underwent conjugation with a gal⁺ strain D)The bacgteria underwent transformation with a wild type

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The presence of bacterial colonies on minimal galactose indicates that the bacteria have taken up a plasmid with the galactose operon, which is not normally present in the galF1F1F1S1^F1F1F10 strain of E.coli. This plasmid likely originated from the wild type F1F1F1S1F1F1F10 phages that were used to infect the cells, which have transferred their DNA to the bacteria via transduction. The presence of the gal⁺ genes on this plasmid allows the bacteria to grow on minimal galactose.

Viruses Are Isolated from Wild TypeE λ\lambdaλ These Viruses Are Used to Infect a Gal- Strain of Infected

Viruses Are Isolated from Wild TypeE $\lambda$ These Viruses Are Used to Infect a Gal^- Strain of Infected