Which of the following statements about codons is true?

The correct choice highlights an important aspect of the genetic code: some codons serve as termination signals during the process of translation. These termination codons, commonly known as stop codons, signal the end of protein synthesis. When a ribosome encounters one of these codons—specifically UAA, UAG, or UGA—it understands that the chain of amino acids being built should be completed, and the newly formed protein is released.

Understanding this is critical in the context of how proteins are synthesized from mRNA, where codons represent sequences of three nucleotides that correspond to specific amino acids or signal terminators in the translation process. Each amino acid is linked to its corresponding codon; however, there are codons that don’t correspond to an amino acid but rather instruct the translation machinery to stop.

The other statements about codons do not accurately reflect the nature of the genetic code. For instance, codons are comprised of three nucleotides rather than four; while some codons can specify the same amino acid due to the redundancy in the genetic code, the notion that all codons are unique to one amino acid is incorrect since there are instances where different codons correspond to the same amino acid. Thus, the emphasis