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Mistake Master · AP Biology · Unit 6 · Step-Through Animation

A Change Is Not a Verdict

You'll learnhow one base change can be silent, missense, nonsense, or a frameshift.

A mutation is a change to the DNA sequence, and that is the whole definition — it says nothing about damage. Watch one base change four different ways in the same little gene, then zoom out to a whole genome and see what mutations usually do, which is nothing at all. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · SILENT · MISSENSE · NONSENSE · FRAMESHIFT · THE CODE IS DEGENERATE · NEUTRAL IS THE DEFAULT · v6

one gene, one base, four outcomes · a change is not a verdict
Before you start
What you're looking at
A row of mRNA bases with one letter changing, then the same 6-codon toy gene mutated four ways. It is deliberately small so a codon and its amino acid fit in one frame; real genes run to hundreds of codons, and the two bar charts are schematic.
The question
What is a mutation, where does it come from, and who ends up inheriting it?
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