What is a codon in molecular genetics?
Answer and explanation
Correct answer: C. A sequence of three consecutive nucleotides on mRNA that specifies a particular amino acid or stop signal
- Step 1: Genetic code is written in triplets. A codon consists of 3 mRNA nucleotides (e.g., AUG = Methionine, UAA = Stop). Step 2. Ribosomes read codons sequentially during translation to assemble amino acids. Answer: A sequence of three consecutive nucleotides on mRNA that specifies a particular amino acid or stop signal. Why not the others: Anticodons are complementary triplets located on tRNA molecules.
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