AP Biology / Unit 6: Gene Expression and Regulation
6.7 Mutations
Notes
Mutations are changes in DNA. They create genetic variation.
- Substitution: silent, missense or nonsense.
- Insertion/deletion: can cause a frameshift.
- Causes: replication errors, radiation, chemicals. Bacteria also gain genes by transformation, transduction and conjugation.
Practice
A mutation turns a codon into a stop codon. This is:
Early stop.
Deleting one base in a coding region usually causes:
Every later codon shifts.
Bacteria picking up DNA from their surroundings is:
Uptake of free DNA.
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