They also have binding sites for antigen, but they are sort of two IgG type molecules bound together by another peptide chain.

同样IgA抗体表面也有与抗原结合位点,但它们就像两个IgG型分子,通过肽链相互连接

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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