What is the role of the ribosome in translation?

• A. Transcribes DNA into RNA
• B. Replicates RNA
• C. Modifies ribosomal RNA
• D. Reads mRNA to produce an amino acid chain

Answer: (D)

Translation is the process by which ribosomes read the messenger RNA sequence and assemble a chain of amino acids into a protein. As the ribosome moves along the mRNA, each codon is matched with the appropriate transfer RNA carrying its amino acid, and peptide bonds form between amino acids to build the polypeptide. This continues until a stop codon is reached, signaling end of the protein.

The other options describe steps outside the ribosome’s role in translation: transcription converts DNA into RNA and is carried out by RNA polymerase; replication (of RNA) is not a standard cellular process like this, since replication typically refers to copying DNA; and modifying ribosomal RNA occurs during rRNA processing and assembly by other cellular components, not by the ribosome's function in translating mRNA.