Question

An HFR strain of E. coli was mixed with an F- strain, and the genotypes are listed below. At various times, samples were removed and agitated to separate the conjugating cells. The first aliquot removed and agitated was designated time 0, and additional samples were removed and agitated at various relative times.

A. To select for ampicillin and lactose resistance.
B. To select for bacteriophage infection.
C. To distinguish different phenotypes.
D. To distinguish between HFR and F- strains.

Answer 1

The main objective of the experiment was to distinguish between HFR and F- strains of E. coli using conjugation and analyze the order of gene transfer between them. By comparing the phenotypes and genotypes of the samples at different time points, it was possible to distinguish between the HFR and F- strains.

Step-by-step explanation:

In this experiment, the main objective was to distinguish between the HFR and F- strains of E. coli by observing the transfer of genetic material through conjugation. The HFR strain, which carries the F plasmid integrated into its chromosome, was mixed with an F- strain. Over time, samples were taken to analyze the order of genes transferred from the HFR strain to the F- strain. By comparing the phenotypes and genotypes of the samples at different time points, it was possible to distinguish between the HFR and F- strains and determine the order of gene transfer.

The main objective of the experiment was to distinguish between HFR and F- strains of E. coli using conjugation and analyze the order of gene transfer between them. By comparing the phenotypes and genotypes of the samples at different time points, it was possible to distinguish between the HFR and F- strains and determine the order of gene transfer.