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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Textbook Question
Chapter 11, Problem 1NST
In the Meselson-Stahl experiment, which of the three modes of replication could be ruled out after one round of replication? after two rounds?
Expert Solution
Summary Introduction
To determine: The reason that in the Meselson– Stahl experiment among the three modes of replication, the mode of replication that could be ruled out after oneround of replication.
Introduction: Messelson and Stahl experiment explained that semiconservative mode of replication used by bacterial cells to produce new DNA molecules.
Explanation of Solution
Messelson grew the E. coli cells for many generations in a medium containing 15NH4Cl. These cells then transferred to 14NH4Cl. After one round of replication, the conservative mechanism of DNA replication was ruled out as the intermediate density of DNA band found in the solution. DNA undergoes the semiconservative mode of replication.
Conclusion
Thus, the conservative mode of replication can be ruled out after one round of replication in case of Meselshon Stahl experiment.
Expert Solution
Summary Introduction
To determine: The reason that in Meselson– Stahl experiment among the three modes of replication the mode of replication that could be ruled out after the second round of replication.
Introduction: Messelson and Stahlstudied the modes of DNA replication in bacteria by using nitrogen and its isotope in the medium. Bands of DNA replication was studied after each round of replication.
Explanation of Solution
Messelson grew the bacterial DNA in N15 and N14 media. After one round of replication in14N media, the band of the intermediate density of DNA was found.
After the second round of replication in14N media, the dispersive model of DNA replication was ruled out. The density of the DNA after the second round of replication was between the intermediate (both dark and light band) and “light” densities of DNA.
Conclusion
Thus, the dispersive model of DNA replication was ruled out after the second round of replication.
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Students have asked these similar questions
In the Meselson Stahl experiment differentiating the possible modes of replication, how many rounds of replication were needed to determine that the following modes of replication were not used in E. coli?
two rounds of replication for conservative; two rounds of replication for dispersive
one round of replication for conservative; two rounds of replication for dispersive
two rounds of replication for conservative; one round of replication for dispersive
one round of replication for conservative; one round of replication for dispersive
none of the above is correct
After two generations of replication in the Meselson and Stahl
experiment, what was the composition of the two bands?
One band was all 14N and one band was half 14N and half 15N.
One band was all 15N and one band was half 14N and half 15N.
One band was all 14N and one band was all 15N.
One band was all 15N and one band was one quarter 14N and three
quarters 15N.
One band was all 14N and one band was one quarter 14N and three
quarters 15N.
In the Meselson-Stahl experiment on DNA replication, what fraction of the DNA was composed of one light strand and one heavy strand ("hybrid") after one generation of growth in medium containing 14N? After two generations of growth in a medium containing 14N? What fraction of hybrid DNA is expected after n generations of growth in a medium containing 14N?
Chapter 11 Solutions
Concepts of Genetics (12th Edition)
Ch. 11 - In the Meselson-Stahl experiment, which of the...Ch. 11 - An alien organism was investigated. When DNA...Ch. 11 - Why might mutations in genes encoding telomerase...Ch. 11 - Although the brother is an immunologically matched...Ch. 11 - Prob. 3CSCh. 11 - HOW DOWE KNOW? In this chapter, we focused on how...Ch. 11 - CONCEPT QUESTION Review the Chapter Concepts list...Ch. 11 - Compare conservative, semiconservative, and...Ch. 11 - Describe the role of 15N in the MeselsonStahl...Ch. 11 - Predict the results of the experiment by Taylor,...
Ch. 11 - What are the requirements for in vitro synthesis...Ch. 11 - In Kornbergs initial experiments, it was rumored...Ch. 11 - How did Kornberg assess the fidelity of DNA...Ch. 11 - Which characteristics of DNA polymerase I raised...Ch. 11 - Kornberg showed that nucleotides are added to the...Ch. 11 - What was the significance of the polA1 mutation?Ch. 11 - Summarize and compare the properties of DNA...Ch. 11 - List and describe the function of the ten subunits...Ch. 11 - Distinguish between (a) unidirectional and...Ch. 11 - List the proteins that unwind DNA during in vivo...Ch. 11 - Define and indicate the significance of (a)...Ch. 11 - Outline the current model for DNA synthesis.Ch. 11 - Why is DNA synthesis expected to be more complex...Ch. 11 - Suppose that E. coli synthesizes DNA at a rate of...Ch. 11 - Several temperature-sensitive mutant strains of E....Ch. 11 - While many commonly used antibiotics interfere...Ch. 11 - Describe the end-replication problem in...Ch. 11 - Many of the gene products involved in DNA...Ch. 11 - In 1994, telomerase activity was discovered in...Ch. 11 - The genome of D. melanogaster consists of...Ch. 11 - Prob. 26ESPCh. 11 - DNA polymerases in all organisms add only 5...Ch. 11 - Assume that the sequence of bases shown below is...Ch. 11 - Reiji and Tuneko Okazaki conducted a now classic...Ch. 11 - Consider the drawing of a dinucleotide below. (a)...Ch. 11 - To gauge the fidelity of DNA synthesis, Arthur...
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- What is meant by semi conservative replication? How did Meselson and Stahl prove it experimentally?arrow_forwardhe Meselson and Stahl experiment provided conclusive evidence for the semiconservative replication of DNA in E. coli. What pattern of bands would they have observed in a CsCl gradient after one generation if replication was conservative? a heavy, a light and an intermediate band one heavy and one light band (no intermediate) one intermediate band one light band one heavy bandarrow_forwardIf the sequence 5′-AACGC-3′ were damaged by reactive oxygen species, what would be the most prevalent product, and what would be the result of replication? (Note: show both strands after replication)arrow_forward
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