Biology A-Level
double helix
What double helix means in Biology A-Level, as defined for AQA.
Definition of double helix
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Reference: AQA
A DNA molecule is a double helix with two polynucleotide chains wound together.
Topics that use double helix
- Structure of DNA and RNA (AQA A-Level)
Related terms
- base sequence
- condensation reaction
- evidence and acceptance
- four bases and twenty amino acids
- hydrogen bonds
- messenger RNA
- nuclear pore
- nucleotide structure
Using double helix in the exam
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