Complementary base pairing
What Complementary base pairing means in Biology GCSE, as defined for AQA, OCR.
Definitions of Complementary base pairing
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Reference: AQA
The bases pair in a specific way: A always pairs with T, and C always pairs with G, holding the two strands of the double helix together.
The bases pair specifically: adenine with thymine, and cytosine with guanine, which holds the two strands together.
The pairing that holds the two strands together, where adenine pairs with thymine and cytosine pairs with guanine.
In the complementary strands a C is always linked to a G on the opposite strand and a T to an A.
The pairs of complementary bases are adenine with thymine (A-T) and guanine with cytosine (G-C).
Bases on opposite strands pair specifically, always A with T and C with G.
Topics that use Complementary base pairing
- DNA and the genome (AQA GCSE)
- DNA structure (biology only) (AQA GCSE)
- What happens in cells (and what do cells need)? (OCR GCSE)
Related terms
- Amino acid sequence
- Base sequence
- double helix
- polymer
- protein folding
- Protein function
- ribosomes
- sugar-phosphate backbone
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