Why was it necessary to culture E. coli for multiple generations in the 14N-rich medium to rule out the dispersive model?
a. Nitrogen is frequently lost by cells during meiosis, so multiple generations were required to ensure that residual-free 15N in the cytoplasm was replaced by 14N from the new medium.
b. Multiple generations were required to ensure that the samples did not contain significant quantities of DNA from other organisms, which would confound the analysis of E. coli DNA.
c. After only a single generation, it was expected that the DNA extracted from E. coli would contain equal proportions of 15N and 14N in both the semi-conservative and dispersive models.
d. Multiple generations of replication in the 14N-rich medium were required to rule out the possibility that the changes to the DNA mass were not the result of inevitable statistical noise.
c. After only a single generation, it was expected that the DNA extracted from E. coli would contain equal proportions of 15N and 14N in both the semi-conservative and dispersive models.
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a. true b. false
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What will be an ideal response?
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