How do bases of the separate strands of DNA molecules associate with each other?

Question

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Answer 1

Hydrogen bonding occurs between a purine base on one strand (adenine or guanine) and a pyrimidine base on the other (thymine or cytosine).

Adenine and thymine can form two hydrogen bonds between each other, whereas guanine and cytosine can form three, making GC rich genomes more stable.

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