Chemistry A-Level
purine with pyrimidine
What purine with pyrimidine means in Chemistry A-Level, as defined for AQA.
Definition of purine with pyrimidine
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Reference: AQA
A two-ring purine always pairs with a one-ring pyrimidine, so every rung is the same width and the helix keeps a constant diameter.
Topics that use purine with pyrimidine
- DNA (A-level only) (AQA A-Level)
Related terms
- 2-deoxyribose
- charged phosphate groups
- complementary base pairing
- hydrogen bonding between bases
- phosphate bridge between sugars
- polar backbone faces water
- alternating backbone
- base sequence stores information
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