Using your knowledge of DNA repair pathways, choose the ...

Question

Using your knowledge of DNA repair pathways, choose the pathway that would be used to repair the following types of DNA damage. Explain your reasoning.

a double-stranded break that occurs during G₁ and prevents completion of DNA replication

Accepted Answer

Welcome back, everyone. Here's our next question. Which of the following is a common form of DNA damage induced by exposure to ultraviolet U V radiation. Choice A base Smiths matches B thymine. Diers C double strand brakes or D single strand breaks. Well, the most common form of DNA damage that's caused by exposure to U V radiation is choice B by mean diers. That's when you form covalent bonds between neighboring pines most commonly thymine. It can be a problem because if there's these covalent bonds between the two neighbors, it can cause them to be treated as a single base in the process of replication. So instead of having say TT in your genetic code, you now will have just a single, it'll be treated as a single T and your complementary strand will have just a single A instead of two A's. So it can introduce errors. And of course, that's essentially do a deletion of a base and that can cause frameshift mutations which are obviously have the potential to cause big problems. So we have identified our common form of DNA damage caused by exposure to U V light. So let's just briefly look at our other answer choices. Um These are not commonly caused by exposure to U V radiation base, mismatches, choice A base mismatches are most often caused by tato of bases. That's when a base takes on temporarily, a different isomeric form that can cause an accidental mismatch pairing with the wrong base. And that often occurs in replication. If it's not caught by proof reading, there's the mismatch repair system which will go through, detect those mismatches and repair them. Then choice C double strand breaks. This is obviously a case of very severe DNA damage, you've completely broken both strands broken a chromosome and that is most commonly introduced by exposure to ionizing radiation. So really high energy radiation as opposed to U V radiation. So things like X rays and gamma rays can introduce those double strand breaks but not what we're looking for. So not our correct answer. And then finally, choice d single strand breaks, again, not caused by ultraviolet radiation, uh usually caused by oxidized bases. So a chemical change to a single base, this can be caused by oxidative stress or erroneous enzyme activity causing this but not caused by U V radiation. So not what we're looking for. So, again, common form of DNA damage induced by exposure to U V radiation. Choice B thymine diers see you in the next video.

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Using your knowledge of DNA repair pathways, choose the pathway that would be used to repair the following types of DNA damage. Explain your reasoning.

a double-stranded break that occurs during G₁ and prevents completion of DNA replication

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Chemistry

Biology

Math

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Programming

Product & Marketing

Using your knowledge of DNA repair pathways, choose the pathway that would be used to repair the following types of DNA damage. Explain your reasoning.a double-stranded break that occurs during G₁ and prevents completion of DNA replication

Using your knowledge of DNA repair pathways, choose the pathway that would be used to repair the following types of DNA damage. Explain your reasoning.

a double-stranded break that occurs during G₁ and prevents completion of DNA replication