In order to have DNA you have to make DNA and your cells are continually making DNA inside your body, through a process of DNA synthesis and that synthesis is occurring because of the presence of an enzyme, a protein called DNA polymerase.

为了使每个细胞都具有DNA,身体通过一个叫做DNA合成的过程,不停的生产DNA,这个合成过程是在,一种酶的催化下进行的,这种酶叫做DNA聚合酶

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