Fill in the missing nucleotides (so there are three per block)...

Question

Fill in the missing nucleotides (so there are three per block) and the missing amino acid abbreviations in the graphic shown here.

Diagram showing DNA, mRNA, tRNA, and amino acids for genetics fundamentals.

Accepted Answer

Hi, everyone. Let's look at our next problem. It says identify the sequence of the template strand of the DNA. And the sequence of M RNA is as follows, we have an M RNA strand written in the five prime three prime direction. So we've got two main things to keep track of here. If we're writing our complementary DNA sequence from left to right, matching base pairs, we're going to need to write that in the three prime to five prime direction if we want to write it from left to right. And the other thing to remember is that while M RNA uses the base Uracil DNA uses based timing in the equivalent spot. So where we see you in R M R N A sequence, the complementary base will be A and then where we see a, the complementary base will be T in our D N A sequence. So with that in mind, we'll take a brief look at our answer choices and we can actually eliminate right away choice A because that has use in it. And we wouldn't expect to see any base you in our D N A strand that's only found in RNA. So choice A can be eliminated. And then choice D also, for the same reason, there's use in it. So we're down to just choices B N C. So now let's look at our strand and we can start to write the complementary DNA sequence. We're not even gonna write the whole thing because we can probably match the first couple bases to see what our correct answer is. We can write more if we need to. So we're gonna start with the three prime end on the left here in our complementary strand and then just match complementary bases. So A and R M RNA strand complementary will be T For you, we'll put a 4G complementary base, see the sea here, we'll put G and then the, to use the complimentary base A A. So now let's look at choice B. Now B is written in the direction five prime, three prime. So we have to start on the right side and read it right to left. Um Since we need to go on three prime to five prime direction, and we see um starting on the right side here that the first three bases are A G T, but we're supposed to have T A C from what we've figured out. So we know that choice B is incorrect. So now we've got choice C, it's written in the direction three prime to five prime. So we can start on the left. And indeed, we see the first three bases, T A C and then the second three bases G A A which correspond to what we figured out for the first six bases. So since that's the only one left, we can go ahead and select choice C for our answer. See you in the next video.

Fill in the missing nucleotides (so there are three per block) and the missing amino acid abbreviations in the graphic shown here.

Key Concepts

DNA Structure and Function

Transcription and mRNA

tRNA and Translation

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