MCAT Biochemistry Question 96: Answer and Explanation
Home > MCAT Test > MCAT biochemistry practice tests
Test Information
- Use your browser's back button to return to your test results.
- Do more MCAT biochemistry practice tests.
Question: 96
6. In the genetic code of human nuclear DNA, one of the codons specifying the amino acid tyrosine is UAC. If one nucleotide is changed, and the codon is mutated to UAG, what type of mutation will occur?
- A. Silent mutation
- B. Missense mutation
- C. Nonsense mutation
- D. Frameshift mutation
Correct Answer: C
Explanation:
UAG is one of the three known stop codons, so changing tyrosine to a stop codon must be a nonsense (or truncation) mutation.