Final answer:
The start codon is AUG, which also specifies the amino acid methionine, while the three stop codons, UAA, UGA, and UAG, do not code for amino acids but signal the termination of protein synthesis.
Step-by-step explanation:
Genetic Code: Start and Stop Codons
In the genetic code, a start codon signals the initiation of protein translation, whereas a stop codon signals its termination. The codon AUG is the most common start codon, which not only signifies the beginning of protein synthesis but also codes for the amino acid methionine. The three stop codons are UAA, UGA, and UAG; these do not code for any amino acids and prompt the release of the nascent polypeptide chain from the ribosome, thus ending the translation process.
One start codon is AUG, which codes for the amino acid methionine. It also serves as the initiation codon to begin translation. One stop codon is UGA, which signals the termination of protein synthesis and does not code for an amino acid.