Topic - Biology: Molecular Basis of Inheritance Step 1: Understanding the Question:
The question asks for a specific sequence of three nucleotides (codon) that has two roles in protein synthesis. Step 2: Detailed Explanation:
The genetic code consists of 64 codons.
1. AUG: This codon has a dual function. It acts as the Initiation Codon (tells the ribosome where to start translation) and it also codes for the amino acid Methionine.
2. Stop Codons: UAA (Ochre), UAG (Amber), and UGA (Opal) are terminator codons. They do not code for any amino acids and signal the end of translation. Step 3: Final Answer:
The codon with dual function is AUG.