Concepts of Genetics (12th Edition)
12th Edition
ISBN: 9780134604718
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino, Darrell Killian
Publisher: PEARSON
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Chapter 6, Problem 16PDQ
A phage-infected bacterial culture was subjected to a series of dilutions, and a plaque assay was performed in each case, with the results shown in the following table. What conclusion can be drawn in the case of each dilution, assuming that 0.1 mL was used in each plaque assay?
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A phagehunter performs a spot titer using standard techniques (3 ul of each dilution spotted to lawn) of a lysate obtained from an optimum webbed plate experiment. The phagehunter counts 4 plaques on the 10-8 dilution spot. Which of the following scenarios is the best choice for the phagehunter to do next?
a.) The phagehunter has not achieved a high enough titer lysate to move forward with characterization experiments, so they should try to make more optimum webbed plates.
b.) The phagehunter has not achieved a high enough titer lysate to move forward with characterization experiments, so they should adopt a phage from direct isolation.
c.) The phagehunter has achieved a high enough titer lysate to move forward with characterization experiments.
d.) The phagehunter has not achieved a high enough titer lysate to move forward with characterization experiments, so they should go back to the pick-a-plaque experiment.
A plaque assay is performed beginning with 1 mL of a solution containing bacteriophages. This solution is serially diluted 3 times by combining 0.1 mL of each sequential dilution with 9.9 mL of liquid medium. Then 0.1 mL of the final dilution is plated in the plaque assay and yields 12 plaques.What is the initial density of bacteriophages in the original 1 mL? Enter your answer to two significant figures ( for example: 1.1 * 10^2)
A phagehunter performs a spot titer using standard techniques (3 ul of each dilution spotted to lawn) of a lysate obtained from an optimum webbed plate experiment. The phagehunter counts 8 plaques on the 10-7 dilution spot. Which of the following scenarios is the best choice for the phagehunter to do next?
a.) The phagehunter has not achieved a high enough titer lysate to move forward with characterization experiments, so they should go back to the pick-a-plaque experiment.
b.) The phagehunter has not achieved a high enough titer lysate to move forward with characterization experiments, so they should adopt a phage from direct isolation.
c.) The phagehunter has not achieved a high enough titer lysate to move forward with characterization experiments, so they should try to make more optimum webbed plates.
d.) The phagehunter has achieved a high enough titer lysate to move forward with characterization experiments.
Chapter 6 Solutions
Concepts of Genetics (12th Edition)
Ch. 6 - When the interrupted mating technique was used...Ch. 6 - In a transformation experiment involving a...Ch. 6 - In complementation studies of the rII locus of...Ch. 6 - A 4-month-old infant had been running a moderate...Ch. 6 - Prob. 2CSCh. 6 - Prob. 3CSCh. 6 - Prob. 4CSCh. 6 - HOW DO WE KNOW? In this chapter, we have focused...Ch. 6 - Review the Chapter Concepts list on p. 123. Many...Ch. 6 - With respect to F+ and F bacterial matings, answer...
Ch. 6 - List all major differences between (a) the F+ F...Ch. 6 - Describe the basis for chromosome mapping in the...Ch. 6 - In general, when recombination experiments are...Ch. 6 - Why are the recombinants produced from an Hfr F...Ch. 6 - Describe the origin of F bacteria and merozygotes.Ch. 6 - In a transformation experiment, donor DNA was...Ch. 6 - Describe the role of heteroduplex formation during...Ch. 6 - Explain the observations that led Zinder and...Ch. 6 - Prob. 12PDQCh. 6 - Two theoretical genetic strains of a virus (abc...Ch. 6 - The bacteriophage genome consists of many genes...Ch. 6 - If a single bacteriophage infects one E. coli cell...Ch. 6 - A phage-infected bacterial culture was subjected...Ch. 6 - In recombination studies of the rII locus in phage...Ch. 6 - In an analysis of rII mutants, complementation...Ch. 6 - If further testing of the mutations in Problem 18...Ch. 6 - Using mutants 2 and 3 from Problem 19, following...Ch. 6 - During the analysis of seven rII mutations in...Ch. 6 - In studies of recombination between mutants 1 and...Ch. 6 - Prob. 23ESPCh. 6 - An Hfr strain is used to map three genes in an...Ch. 6 - A plaque assay is performed beginning with 1 mL of...Ch. 6 - In a cotransformation experiment, using various...Ch. 6 - For the experiment in Problem 26, another gene, g,...Ch. 6 - Bacterial conjugation, mediated mainly by...Ch. 6 - A study was conducted in an attempt to determine...
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- what are the volume dilution and dilution factor for bacteriophage A，B，Carrow_forwardA plaque assay is performed beginning with 1 mL of a solution containing bacteriophages. This solution is serially diluted 4 times by combining 0.1 mL of each sequential dilution with 9.9 mL of liquid medium. Then 0.1 mL of the final dilution is plated in the plaque assay and yields 21 plaques. What is the initial density of bacteriophages in the original 1 mL? Recall that initial phage density = (plaque number/mL) ×× (dilution factor).arrow_forwardYou are counting plaques on your plaque assay plates made from serial dilutions of your high titer lysate. Your 10-5 plate has 615 plaques although some are butting up against each other so it is difficult to get an accurate count. Your 10-6 plate has 42 plaques, and your 10-7 plate has only 1 plaque. Which plate would probably yield the most accurate titer calculation of your phage and why is it more trustworthy than the others?arrow_forward
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