Here's why:
* AUG codes for the amino acid methionine.
* It serves as both a start codon and a codon for methionine.
* This means that every protein synthesis process begins with a methionine residue.
Important note: While AUG is the primary start codon in most organisms, there are some exceptions. In some cases, other codons can act as alternate start codons, but AUG remains the most common and important one.
