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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Well, one way to think about is they have more antigen binding sites and so they're going to be more efficient at neutralizing the pathogen on a per-molecule basis than IgG is.

可以这么考虑,因为IgM表面有更多的抗原结合位点,所以相对于IgG,IgM在分子层面上,能够更为有效地与病原体结合

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