What are the four distinct stages of translation?

What are the four distinct stages of translation?

• A. initiation, elongation, translocation, termination
• B. initiation, transcription, elongation, termination
• C. initiation, elongation, termination, replication
• D. initiation, translation, elongation, termination

Answer: (A)

Translation proceeds through four stages: initiation, elongation, translocation, and termination. In initiation, the ribosome assembles at the start codon with the mRNA and initiator tRNA, establishing the reading frame for the message. During elongation, aminoacyl-tRNAs bring amino acids to the ribosome and a peptide bond forms, growing the polypeptide one amino acid at a time. Translocation is the ribosome’s movement along the mRNA by one codon, shifting the tRNAs from the A site to the P site and then to the E site, so the next codon can be read. Termination occurs when a stop codon enters the A site; release factors promote release of the finished polypeptide and the ribosome dissociates. This four-stage view highlights both the chemical steps of building the chain and the physical movement of the ribosome along the mRNA. For contrast, transcription is RNA synthesis from DNA, and replication is DNA copying, neither of which is translation.

Translation proceeds through four stages: initiation, elongation, translocation, and termination. In initiation, the ribosome assembles at the start codon with the mRNA and initiator tRNA, establishing the reading frame for the message. During elongation, aminoacyl-tRNAs bring amino acids to the ribosome and a peptide bond forms, growing the polypeptide one amino acid at a time. Translocation is the ribosome’s movement along the mRNA by one codon, shifting the tRNAs from the A site to the P site and then to the E site, so the next codon can be read. Termination occurs when a stop codon enters the A site; release factors promote release of the finished polypeptide and the ribosome dissociates. This four-stage view highlights both the chemical steps of building the chain and the physical movement of the ribosome along the mRNA. For contrast, transcription is RNA synthesis from DNA, and replication is DNA copying, neither of which is translation.