You can do that by gently adding heat and making it basic, but you make the two DNA strands separate.

你可以通过逐渐加温并使之碱化的方法,使双链DNA解旋

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You first separated your DNA, let the primers bind, then turn on the enzyme, and it makes copies of each one of these.

首先解旋DNA双链,使引物结合,接着激活聚合酶,最终得到各链的复制产物

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The DNA molecule here has been spread apart, opening up two single stranded DNA's which have complementary base sequences because they were double stranded DNA.

这里DNA分子被分开,形成两条单链DNA,这两条单链碱基序列互补,因为它们是由双链DNA解旋形成的

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