Question: The lac repressor protein controls expression of the lac operon by A) binding to the lacZ and lac…
Show transcribed image text The lac repressor protein controls expression of the lac operon by A) binding to the lacZ and lacY genes to repress transcription. B) binding to the lac promoter site to repress transcription. C) binding to the lac promoter site to repress translation. D) binding to the lac operator site to repress transcription. E) binding to the lac operator site to repress translation. 2. The 1952 experiment performed by the Lederbergs in which they replica-plated ten million colonies of T1 -phage sensitive E. coli to plates containing high concentrations of T1 phage and found a small number of phage-resistant colonies showed that: A) a selecting agent can affect mutation rate in E. coli. B) mutations can arise spontaneously before exposure to the selecting agent. C) mutations in E. coli occur at a relatively high frequency. D) the mutation rate in E. coli fluctuates greatly from one generation to the next. E) the T1 phage can act as a mutagen as well as a selecting agent in E. coli. 3. Oswald Avery and colleagues strengthened scientific support that DNA was the transforming factor by replicating the Griffith experiment with some important differences in experimental design. The key difference was: A) purifying "S strain" DNA and RNA from other biomolecules. B) systematically eliminating the impact of classes of "S strain" biomolecules (e.g., lipids, sugars, proteins etc.) using enzymatic digestion before mixing with "R strain" live cells. C) injecting "S strain" DNA directly into "R strain" cells and observing the change in phenotype. D) A very used Escherichia coli rather than Streptococcus as it is easier to transform. E) all of the above. 4. The complexity of discontinuous (lagging) strand replication is necessary because: A) there is room for only a single DNA polymerase III enzyme in the replisome B) the helicase can only unwind double helical DNA slowly C) as polymerization occurs only in the 5' to 3' direction, the lagging (discontinuous) strand must be synthesized in consecutive small fragments D) the RNA primase works better on the leading (continuous) strand DNA E) DNA polymerase I is more often associated with the lagging (discontinuous) strand
The lac repressor protein controls expression of the lac operon by A) binding to the lacZ and lacY genes to repress transcription. B) binding to the lac promoter site to repress transcription. C) binding to the lac promoter site to repress translation. D) binding to the lac operator site to repress transcription. E) binding to the lac operator site to repress translation. 2. The 1952 experiment performed by the Lederbergs in which they replica-plated ten million colonies of T1 -phage sensitive E. coli to plates containing high concentrations of T1 phage and found a small number of phage-resistant colonies showed that: A) a selecting agent can affect mutation rate in E. coli. B) mutations can arise spontaneously before exposure to the selecting agent. C) mutations in E. coli occur at a relatively high frequency. D) the mutation rate in E. coli fluctuates greatly from one generation to the next. E) the T1 phage can act as a mutagen as well as a selecting agent in E. coli. 3. Oswald Avery and colleagues strengthened scientific support that DNA was the transforming factor by replicating the Griffith experiment with some important differences in experimental design. The key difference was: A) purifying "S strain" DNA and RNA from other biomolecules. B) systematically eliminating the impact of classes of "S strain" biomolecules (e.g., lipids, sugars, proteins etc.) using enzymatic digestion before mixing with "R strain" live cells. C) injecting "S strain" DNA directly into "R strain" cells and observing the change in phenotype. D) A very used Escherichia coli rather than Streptococcus as it is easier to transform. E) all of the above. 4. The complexity of discontinuous (lagging) strand replication is necessary because: A) there is room for only a single DNA polymerase III enzyme in the replisome B) the helicase can only unwind double helical DNA slowly C) as polymerization occurs only in the 5' to 3' direction, the lagging (discontinuous) strand must be synthesized in consecutive small fragments D) the RNA primase works better on the leading (continuous) strand DNA E) DNA polymerase I is more often associated with the lagging (discontinuous) strand
