The start codon of an mRNA specifies which of the following amino acids?

• A. Valine
• B. Leucine
• C. Methionine
• D. Glycine

Answer: (C)

Verified step by step guidance

1. Understand that the start codon is a specific sequence of three nucleotides in mRNA that signals the start of protein synthesis.
2. Recall that the most common start codon in mRNA is 'AUG'.
3. Know that the codon 'AUG' codes for the amino acid Methionine.
4. Recognize that Methionine is the amino acid that is typically specified by the start codon in eukaryotic cells.
5. Conclude that the start codon of an mRNA specifies the amino acid Methionine, which is essential for initiating protein synthesis.