Final answer:
An mRNA codon is complementary to the DNA triplet, and during transcription, the DNA sequence is used to create an mRNA strand with uracil replacing thymine. Each codon on mRNA specifies an amino acid or a stop signal in protein synthesis.
Step-by-step explanation:
A messenger RNA (mRNA) codon is complementary to the DNA triplet. In the process of transcription, the sequence of the DNA is used as a template to create an mRNA strand.
The mRNA sequence is complementary to the DNA sequence, with uracil (U) replacing thymine (T).
For example, if the DNA strand has a sequence 5'-AATTGCGC-3', the sequence of the complementary RNA is 3'-UUAACGCG-5'.
Each codon, which is a consecutive sequence of three nucleotides on an mRNA molecule, corresponds to a specific amino acid or to a signal to terminate the polypeptide chain during translation.
Anticodons, on the other hand, are found on transfer RNA (tRNA) and are sequences that are complementary to the codons on mRNA.