It has to do with the nature of this complementary binding between double stranded DNA and the fidelity of this base pair matching in forming stable DNA molecules.

这些特性能从根本上解释,为何DNA双链的碱基能互补配对,以及在形成稳定的DNA分子结构时,碱基互补配对为何具有一致性

耶鲁公开课 - 生物医学工程探索课程节选

Now DNA is a double helix and I've only shown you one part of the helix, right? I've shown you one upright strut and a base hanging off of it, but it forms a double helix because complementary strands of DNA strongly associate with one another and that's a very stable structure.

NA是双螺旋,我只是给你们讲了螺旋的一边,我给你们演示,一条链的支柱及碱基团,但其能构成双螺旋,是因为DNA是完全互补的两条链,彼此之间结合紧密,结构异常稳定

耶鲁公开课 - 生物医学工程探索课程节选