A particular Hfr strain normally transmits the pro+marker as the last one in conjugation. In a cross of thisstrain with an F− strain, some pro+ recombinants are recovered early in the mating process. When these pro+cells are mixed with F−cells, the majority of the F− cellsare converted into pro+ cells that also carry the F factor.Explain these results.

A particular Hfr strain normally transmits the pro+marker as the last one in conjugation. In a cross of thisstrain with an F− strain, some pro+ recombinants are recovered early in the mating process. When these pro+cells are mixed with F−cells, the majority of the F− cellsare converted into pro+ cells that also carry the F factor.Explain these results.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter17: Bacterial And Viral Genetics

Section: Chapter Questions

Problem 1ITD

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An Hfr strain that is leuA+ and thiL+ was mixed with a strain thatis leuA− and thiL−. In the data points shown in the following graph,the conjugation was interrupted at different time points, and thepercentage of recombinants for each gene was determined bystreaking on a medium that lacked either leucine or thiamine.What is the map distance (in minutes) between these two genes?
Why are the recombinants produced from an Hfr * F- cross rarely, if ever, F+?
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An Hfr strain that is leuA+ and thiL+ was mixed with a strain thatis leuA− and thiL−. In the data points shown in the following graph,the conjugation was interrupted at different time points, and thepercentage of recombinants for each gene was determined bystreaking on a medium that lacked either leucine or thiamine.What information do you know based on the question and your understanding of the topic?
An Hfr strain that is leuA+ and thiL+ was mixed with a strain thatis leuA− and thiL−. In the data points shown in the following graph,the conjugation was interrupted at different time points, and thepercentage of recombinants for each gene was determined bystreaking on a medium that lacked either leucine or thiamine.Make a calculation.
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