How does translation terminate?

How does translation terminate?

• A. Stop codon is recognized by release factors, which promote hydrolysis of the polypeptide from the tRNA and dissociation of the ribosome.
• B. Aminoacyl-tRNA binds the stop codon.
• C. mRNA is degraded.
• D. Ribosome swaps tRNAs.

Answer: (A)

Translation ends when the ribosome encounters a stop codon in the mRNA. Release factors recognize this stop codon and bind in the ribosome, triggering the hydrolysis of the bond between the newly made polypeptide and the tRNA in the P site. That releases the finished protein. Afterward, the ribosome separates into its subunits, and the mRNA and tRNAs are released, so the components can be reused. The idea that a tRNA would bind a stop codon isn’t correct because stop codons aren’t read by tRNAs. Degrading the mRNA happens separately from termination, and a process like swapping tRNAs isn’t how termination operates.

Translation ends when the ribosome encounters a stop codon in the mRNA. Release factors recognize this stop codon and bind in the ribosome, triggering the hydrolysis of the bond between the newly made polypeptide and the tRNA in the P site. That releases the finished protein. Afterward, the ribosome separates into its subunits, and the mRNA and tRNAs are released, so the components can be reused. The idea that a tRNA would bind a stop codon isn’t correct because stop codons aren’t read by tRNAs. Degrading the mRNA happens separately from termination, and a process like swapping tRNAs isn’t how termination operates.