Question

Which of the following statements about translational termination is correct?A. Accessory proteins called elongation factors recognize the stop codon in the mRNA to terminate translation.
B. The ribosome keeps translating until it reaches the end of the mRNA and falls off the transcript.
C. Peptidyl transferase breaks the bond between the growing polypeptide chain and the tRNA in the P site, but there is no new charged tRNA in the A site, which results in the termination of translation and release of the polypeptide.
D. A special stop-tRNA enters the A site and terminates translation.
E. Rho proteins bind to the mRNA when the ribosome pauses and stops translation.

Answer 1

Answer:

C

Explanation:

The correct answer here would be that the peptidyl transferase breaks the bond between the growing polypeptide chain and the tRNA in the P site, but there is no new charged tRNA in the A site, which results in the termination of translation and release of the polypeptide.

The translation process stops when the stop codon in the mRNA being translated enters site A in the translation complex. When this happens, the release factor recognizes the stop codon and makes the enzymes that form peptide bonds to add water to the last amino acid on the chain.

The addition of water leads to the breaking of the peptide bond by peptidyl transferase, causing the separation of the polypeptide chain from the tRNA and the eventual release of the protein.

Hence, the correct option would be C.