Final answer:
During translation, the mRNA's genetic code is read three bases at a time, which form units called codons; each codon stands for a specific amino acid.
Step-by-step explanation:
During translation, the genetic code on the mRNA is read three bases at a time in units called codons. This reading determines the order in which amino acids are assembled into a protein. For example, the codon AAU stands for the amino acid asparagine. Each codon specifies one amino acid, though some codons act as start or stop signals for protein synthesis.