Final answer:
The mRNA bases AUG, CUG, ACC, and UAG correspond to methionine (also the start codon), leucine, threonine, and a stop codon, respectively.
Step-by-step explanation:
The mRNA bases corresponding to the given codons are as follows:
AUG corresponds to the amino acid methionine, and it is also the start codon for translation.
CUG corresponds to the amino acid leucine.
ACC corresponds to the amino acid threonine.
UAG is a stop codon; it does not code for an amino acid and signals the termination of protein synthesis.
A codon is a sequence of three mRNA bases that encodes either an amino acid or a signal for translation to start or stop.