Question

4a. Define semi-conservative DNA replication. 4b. Explain why Recombinational Repair of thymidine dimers absolutely requires active DNA replication. 5a. Explain how the Ames Test works to identify whether a novel chemical (compared to water) is a DNA mutagen. b. Below, draw the plate results that would allow you to conclude that this novel chemical was in fact a mutagen compared to a plate with water as a negative control.

Answer 1

4a)

Semi-concervative DNA replication defines the DNA replication mechanisms in every cells. It is so called because, of the generation of two copies of original DNA, each of them having an original & a newly produced strand. The DNA replication is semi-concervative due to the fact that one strand of the original DNA is conserved during the production of a new DNA molecule. Here, an existing strand is utilized to produce a new DNA strand.

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