When a codon in an mRNA with the sequence 5'-UAA-3' enters the A site of a ribosome, it is not recognized by a tRNA with a complementary anticodon. Why not? What recognizes it instead?

Video transcript

Hi everyone. Let's take a look at this practice problem together. Which of the following code ins will not be recognized by A T R N A. So this question is referencing translation and what do we know about translation? N T E r N A while translation is the process where cell takes an M RNA strand and converts that to amino acids or polyp peptides. Well how does it do this? It does it using a T RNA molecule and the T RNA is basically an adapter molecule. It's responsible for bringing amino acids to the machinery. The cell machinery used to make polyp peptides. Now recall that in translation. One coat on is representative of one amino acid except stop code ons. So there is an exception. So stop code ons do not make amino acids. They tell the cell at that point to terminate translation. So out of our answer choices we have three code ins given. So let's reference a genetic code table and see if any of these are stock options. So here we have our genetic code table, option A. We have you A. Which is indeed a stop code on. Then we have B. U. G. A. Which is also a stop code on. And lastly C. Is you A G. And that is also a stop code on. So all of them are stop code ons. So they will not be recognized by A T E R N A. And so D All of the above is the correct answer. Alright everyone. I hope you found this helpful and I'll see you soon for the next practice problem.