Chemistry A-Level
complementary base pairing
What complementary base pairing means in Chemistry A-Level, as defined for AQA.
Definition of complementary base pairing
Check what you remember
Read the wording for your board, then hide it and explain complementary base pairing in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
Adenine always hydrogen bonds to thymine, and cytosine always to guanine, so the sequence of one strand fixes the sequence of the other.
Topics that use complementary base pairing
- DNA (A-level only) (AQA A-Level)
Related terms
- 2-deoxyribose
- charged phosphate groups
- hydrogen bonding between bases
- phosphate bridge between sugars
- polar backbone faces water
- purine with pyrimidine
- alternating backbone
- base sequence stores information
Using complementary base pairing in the exam
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