9). E. coli strain B was coinfected with two phage strains: one having a large clear plaque (hr) phenotype and the other with a small turbid (h+r+) phenotype. Locus h regulates the host range and locus r regulates the rate of lysis. The progeny phages were collected and plated on a mixed culture of E coli B and B/2. Use the table below to answer the following questions. Plaque Morphology Large, clear Small, turbid Small, clear Large, turbid Frequency 615 593 95 84 Genotype a). Do you need the rule of 2 in this case? Why or why not? b). What are the genotypes of each progeny and which genotypes are parental vs. recombinant? c). Calculate the frequency of recombination (not map distance) between the h and r loci. Use two decimal places in your answer.

9). E. coli strain B was coinfected with two phage strains: one having a large clear plaque (hr) phenotype and the other with a small turbid (h+r+) phenotype. Locus h regulates the host range and locus r regulates the rate of lysis. The progeny phages were collected and plated on a mixed culture of E coli B and B/2. Use the table below to answer the following questions. Plaque Morphology Large, clear Small, turbid Small, clear Large, turbid Frequency 615 593 95 84 Genotype a). Do you need the rule of 2 in this case? Why or why not? b). What are the genotypes of each progeny and which genotypes are parental vs. recombinant? c). Calculate the frequency of recombination (not map distance) between the h and r loci. Use two decimal places in your answer.

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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