Final answer:
The initiation codon, AUG, establishes the reading frame of the genetic code.
Step-by-step explanation:
The initiation codon, AUG, establishes the reading frame of the genetic code. It is also known as the start codon. After the start codon, the next three bases are read as the second codon, and so on until a stop codon is reached. The reading frame determines how the bases are divided into codons.
For example, after the AUG start codon, if the next three bases are read as UCU, it would form the second codon. The next three bases after that would form the third codon, and so on.