Concepts of Genetics (11th Edition)
11th Edition
ISBN: 9780321948915
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino
Publisher: PEARSON
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Chapter 6, Problem 17PDQ
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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Shown below is a set of cell culture plates for a plaque assay. The assay was performed by preparing dilutions of a virus stock with the dilution factor for each prepared dilution listed below the sample. 0.5 mls of each dilution was added to confluent (fully covered) monolayers of cells on each plate. The virus used for the assay had a titer of 2 x 1010 Plaque forming units (PFU) per ml.
Only 1 set of the above plates would have a number of plaques on it that would be both easy to count and high enough to be statistically relevant. Which dilution set would it be and about how many plaques would there be on the plates of that dilution set.
3) Were all of the conditions of a standardized
Kirby-Bauer test met as you performed this assay?
If not, which were not?
4) What is the significance of colonies that develop
within otherwise clear zones of inhibition? If the
laboratory report for one of your patients indicated
colonies within the zone, what concerns would you
have for your patient?
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.
Chapter 6 Solutions
Concepts of Genetics (11th 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 - Prob. 1CSCh. 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 - Prob. 13PDQCh. 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. 24ESPCh. 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...Ch. 6 - Prob. 31ESP
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