A gene mutation changes a single nucleotide so that a codon for one amino acid codes for a different amino acid. What is this called?
Answer and explanation
Correct answer: D. Missense mutation
- Step 1: One base is substituted.
- Step 2: The codon now codes for a different amino acid: a missense mutation.
Answer
Missense mutation.
Why not the others: Nonsense mutation: this creates a stop codon. Frameshift mutation: this changes the reading frame by insertion or deletion. Silent mutation: the amino acid sequence would be unchanged.
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