Biology GCSE
double helix
What double helix means in Biology GCSE, as defined for AQA, OCR.
Definitions of double helix
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Reference: AQA
The arrangement in which the bases project from the backbone and form hydrogen bonds with bases on the opposite strand produces the double helix.
Two separate polynucleotide strands running in opposite directions, wound around a central axis to establish a spiral.
Topics that use double helix
- DNA structure (biology only) (AQA GCSE)
- What happens in cells (and what do cells need)? (OCR GCSE)
Related terms
- Amino acid sequence
- Complementary base pairing
- polymer
- protein folding
- ribosomes
- sugar-phosphate backbone
- transcription
- translation
Using double helix in the exam
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