In this chapter, we focused on how DNA is replicated and synthesized. We also discussed recombination at the DNA level. Along the way, we encountered many opportunities to consider how this information was acquired. On the basis of these discussions, what answers would you propose to the following fundamental questions? What is the experimental basis for concluding that DNA replicates semiconservatively in both bacteria and eukaryotes?

Video transcript

Hey everyone. Let's take a look at this question together. The mode of replication in which each replicated DNA molecule would consist of one old and one new strand is called. Which so let's recall the different modes of replication to try to figure out which one here best describes. That mode in which each replicated molecule consists of one old and one new strand. Well immediately we can go ahead and cross off answer choice D. Because we know that there is no such thing as a semi disperse it mode of replication because semi disperse it is not real. And so now we only have to decide between answer choices A. B. And C. So looking at answer choice is A. And B. We know that A. Is conservative but B says semi conservative which in this case that conservative mode of replication we have that the double helix of D. N. A. It separates replicates meaning we get one old strand and one new strand. However it is the old Felix that reforms. Whereas in the semi conservative mode of replication each strand serves As a template or a new strand and after replication we get one old and one new, which means that the mode of replication in which each replicated DNA molecule would consist of that one old and that one new strand is answer choice B. Semi conservative and not answer a conservative because in that conservative mode of replication the old helix reforms whereas in semi conservative each strand serves as a template for a new strand and we end up with one old strand and one new strand instead of that old helix reforming And lastly, answer choice C. Is incorrect because disperse. It means that we have some old and some new sections in that replicated D. N. A. So it is not disperse it and then semi disperse. It is not real. So answer Choice B. Semi conservative is the correct mode of replication in which each replicated DNA molecule would consist of one old and one new strand. I hope you found this video to be helpful. Thank you and goodbye.