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How does messenger RNA direct the order of amino acids in a protein?

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Peptide — Protein The molecular structure of a peptide (a small protein) consists of a sequence of amino acids.

Messenger RNA (mRNA) directs the order of amino acids in a protein through a process called translation, which occurs on ribosomes within the cell.12

The mRNA molecule carries the genetic code as a sequence of nucleotides. This message is read in "words" of three nucleotides known as codons. Each codon specifies a particular amino acid or acts as a signal to terminate protein synthesis.13

The process functions as follows:
* Reading the Code: The ribosome reads the mRNA sequence three bases at a time, starting from the 5' end toward the 3' end.12
* Decoding via tRNA: Transfer RNA (tRNA) molecules act as intermediaries. Each tRNA carries a specific amino acid and binds to the mRNA codon that corresponds to that amino acid.42
* Chain Assembly: As the ribosome moves along the mRNA, it facilitates the formation of peptide bonds between the amino acids brought by the tRNAs, linking them into a growing polypeptide chain.42
* Termination: Translation concludes when the ribosome encounters a stop codon (UAG, UAA, or UGA), causing the completed protein to dissociate from the machinery.13