Gene Mutations

42 questions on this block. Tap an answer and it moves on by itself — correct answers advance immediately, misses hold a few seconds so you can read why.

The key idea Compare the lengths to name the mutation. A substitution changes one base in one codon; use the chart to check its effect. A single-base insertion or deletion shifts the reading frame. Extra practice also considers a substitution that ends the protein early.

Warm-up · not scored

Click the buttons and watch what changes.

Compare the lengths. A substitution keeps the same number of bases. Adding or deleting one base shifts the reading frame: a frameshift.

Part 1Substitution, insertion, or deletion?

Part 2Silent, missense, or nonsense?

Part 3The reading frame and frameshift mutations

Part 4Point mutation or frameshift: predict the protein

Part 5From a DNA change to a trait

Part 6Positive, negative, or no effect

Gene Mutations

Warm-up · not scored

Review Complete

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