Two amino acids are linked by a peptide bond when....?

Two amino acids are linked by a peptide bond when:


a. two ribosomes attach simultaneiously to the same mRNA transcript.


b. two tRNAs pair with neighboring codons on an mRNA transcript.


c. two codons on an mRNA transcript bind to each other.


d. a ribosome attaches to two codons on an mRNA transcript.








PLEASE help me with this biology question. It is due tomorrow. Thank you to all that took the time to help me too.





one more thing..... please tell me how you got the answer in a very brief summary, and dont forget to tell me what the answer is.





for example : answer= d. a ribosome attaches to two codons on an mRNA transcript.





im telling you to do this because some ppls that answer tell me how they got the answer but forget to mention what it is.





THANK YOU SOOOOO MUCH TOO!

Two amino acids are linked by a peptide bond when....?
b. two tRNAs pair with neighboring codons on an mRNA transcript.





tRNAs bring the appropriate amino acids to the mRNA codons, and join them together as the ribosome moves along the mRNA.





EDIT:





The guy below me posted a good point, the peptide bond formation, is catalyzed by a ribozyme, peptidyltransferase, an activity intrinsic to the 23S rRNA in the 50s ribosomal subunit. But this question if obviously over-simplified, I think the more accurate answer would be B since ribosome attachment to the mRNA results in no peptide bond formation initially. Only when the tRNAs bring the amino acids to the appropriate sites do peptide bonds begin to form
Reply:Ans: d. a ribosome attaches to two codons on an mRNA transcript.





Explanation:


tRNA simply brings amino acid grp to the mRNA but doesn't bind them together. Instead, the ribosome will bind them together as it moves along the mRNA

hooks