The final phase of translation is called which of the following?

• A. Initiation
• B. Elongation
• C. Termination
• D. Translocation

Answer: (C)

Termination is the end stage of translating mRNA into a protein. It occurs when a stop codon shows up in the ribosome’s A site. Stop codons don’t code for amino acids, so no tRNA binds them. Instead, release factors bind and trigger hydrolysis that releases the finished polypeptide from the tRNA in the P site. Once the polypeptide is released, the ribosomal subunits, the mRNA, and the release factors dissociate, and the ribosome is recycled for another round of translation. For contrast, initiation is when the ribosome assembles at the start codon, and elongation is the ongoing addition of amino acids with translocation moving the ribosome along the mRNA during that process.