This bacteriophage DNA molecule has been warmed. Label the portions that likely have a higher ratio of GC base pairs and the portions that have a higher ratio of AT base pairs.

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Question

This bacteriophage DNA molecule has been warmed. Label the portions that likely have a higher ratio of GC base pairs and the portions that have a higher ratio of AT base pairs.

Accepted Answer

Hi, everyone. And welcome back. Our next problem says an experiment was conducted on a bacterial DNA strand by exposing it to high temperature conditions, determine which sections would most probably consist of larger amounts of guanine cytosine or GC pairing. And which ones would consist mainly of adenine thymine or A T pairings. A. The sections where separation occurs rapidly should be rich in guanine cytosine or GC. The parts remaining closely bonded even after exposure should mostly comprise guanine cytosine GC. See the parts remaining closely bonded even after exposure should mostly comprise adenine thymine or A T or D. All parts will equally comprise both types of bases. So we can recall that heating DNA denatures it and recall that the more stable the bonds, the more energy you'll have to put into breaking them. In this case, heat energy. So we need to think about which bonds would be more stable. The GT or the, the GC excuse me or the A T. Well, recall these are hydrogen bonds, not chemical bonds between things, but we can remember a quick difference between them, which is that the GC pairings are joined by three hydrogen bonds. I put three H bonds while the A T pairings are joined by only two hydrogen bonds. So the GC pairings are going to be the stronger bond. So given that those GC pairings are more strongly linked together, that means that choice B, the parts remaining closely bonded even after exposure should mostly compromise. Guanine mostly comprise, excuse me, guanine, cytosine or GC. It'll take more heat comparably to break those three hydrogen bonds than the two hydrogen bonds in the A T pairings. When we look at our other answer, choices, choice A, the sections where separation occurs rapidly should be rich in guanine. Well, we'd expect that to be rich in A T pairings otherwise because the A T with their two hydrogen bonds will separate more quickly. That's why to A is incorrect to C the parts remain closely bonded even after exposure should mostly comprise adenine thymine or A T. Well, this is incorrect because again, same reason, that's the three hydrogen bonds of the GC pairings will be stronger and thus stay together even with some heat exposure. And then choice D all parts will equally comprise. Well, we know we can roll that given that we rather quickly came up with some differences between these pairings. So if you have a bacterial DNA strand and you're exposing it to high temperature, our description here of this behavior says that the parts remaining completely closely bonded even after exposure should mostly comprise guanine cytosine or GC. And that answer is choice B and we'll see you in the next video.

This bacteriophage DNA molecule has been warmed. Label the portions that likely have a higher ratio of GC base pairs and the portions that have a higher ratio of AT base pairs.

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Verified Solution

Key Concepts

GC and AT Base Pairing

DNA Melting Temperature

Bacteriophage Structure

This bacteriophage DNA molecule has been warmed. Label the portions that likely have a higher ratio of GC base pairs and the portions that have a higher ratio of AT base pairs. <IMAGE>

Verified Solution

Key Concepts

GC and AT Base Pairing

DNA Melting Temperature

Bacteriophage Structure

This bacteriophage DNA molecule has been warmed. Label the portions that likely have a higher ratio of GC base pairs and the portions that have a higher ratio of AT base pairs.

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