A codon on mRNA specifies which of the following?

A codon on mRNA specifies which of the following?

• A. The amino acid
• B. A nucleotide
• C. A sugar
• D. The phosphate group

Answer: (A)

Codons on mRNA specify which amino acid will be added next during protein synthesis. A codon is a triplet of nucleotides that the ribosome reads to determine the correct amino acid, and the genetic code maps each triplet to a specific amino acid (or a stop signal). The sugar and phosphate are parts of the RNA backbone and do not determine which amino acid is incorporated. A single nucleotide isn’t what the codon specifies; it’s the three-nucleotide sequence that directs the amino acid identity. So the best answer is that the codon encodes the amino acid.

Codons on mRNA specify which amino acid will be added next during protein synthesis. A codon is a triplet of nucleotides that the ribosome reads to determine the correct amino acid, and the genetic code maps each triplet to a specific amino acid (or a stop signal). The sugar and phosphate are parts of the RNA backbone and do not determine which amino acid is incorporated. A single nucleotide isn’t what the codon specifies; it’s the three-nucleotide sequence that directs the amino acid identity. So the best answer is that the codon encodes the amino acid.