Biology A-Level
third base position
What third base position means in Biology A-Level, as defined for AQA.
Definition of third base position
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Reference: AQA
The position at which codons for the same amino acid often differ, so a substitution there is the most likely to be silent.
Topics that use third base position
Related terms
- alleles
- chemical mutagens
- chromosome content diagrams
- crossing over
- degenerate code
- frameshift
- genetic variation
- independent segregation
Using third base position in the exam
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