If you have DNA fragments, so this is DNA that you've cut up into fragments using restriction enzymes for example.

如果你有DNA片段,例如有一段你用限制酶,切割成片段的DNA

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Now another property of restriction enzymes is that they always cut the DNA in the same way.

限制性内切酶的另一个特性是,总是以同样的方式切割DNA

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Restriction enzymes are just a kind of enzyme, enzymes are protein molecules that make a chemical reaction go faster, and the chemical reaction that restriction enzymes do is cutting DNA.

限制性内切酶是一种酶,而酶是加速化学反应的蛋白质分子,限制性内切酶加速的化学反应,是切割DNA

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