What component in a nucleic acid determines the 5' free end?

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All right. Hello everyone. So this question is asking us what component in a nucleic acid determines the five prime free N option A says the nitrogenous base attached to the three prime carbon B says the phosphate group attached to the five prime carbon C says the hydroxyl group attached to the three prime carbon. And D says the phosphate group attached to the three prime carbon. So to understand the structural component of a nucleic acid, we have to understand the structure of the nucleotides that make up nucleic acids. So for this demonstration, let's do DNA nucleotides and then we'll discuss the difference between DNA and RN A. So first, the component to either A DNA or an RN A nucleotide is the sugar backbone. Now, it's the sugar backbone that changes depending on whether or not the nucleotides in question, make up DNA or RN A. Because this example, for this example, we're talking about DNA, the sugar backbone is deoxyribose. So on the three prime carbon of the ring itself is a hydroxy group. The reason it's called deoxyribose is because the two prime carbon does not have a hydroxy group. So thats the first component. The other component is the nitrogenous space that's attaching to the one prime carbon of the sugar backbone. Now, the nitrogenous base can also change depending on whether or not we're talking about DNA or RN A, for example, DNA has thymine, whereas RNA has IL and last but not least we have a phosphate group in our nucleotide as well. So the nucleotide is attaching to the five prime carbon of the sugar backbone. And it's important to recognize that the five prime carbon is actually outside of the ring. So going back to the question at hand, it's asking what component determines the five prime free end. And the answer would simply be the phosphate group that's attaching to the five prime carbon. And just to go ahead and clarify a step further recall that DNA nucleotides and RN A nucleotides for that matter are connecting to each other from five prime to three prime. This means that the five prime os fate group is attaching itself to the three prime hydroxy group of the previous nucleotide. This is what ultimately creates the structure of the larger nucleic acid. So even still, we can recognize here that the five prime free end of the nucleic acid is the phosphate group attaching to that five prime carbon. So our answer is going to be option B as in boy and there you have it. So with that being said, thank you so very much for watching. And I hope you found this helpful.

What component in a nucleic acid determines the 5' free end?

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Key Concepts

Nucleic Acid Structure

5' and 3' Ends

Phosphate Group