The reason that 3' is important is that when you polymerize two nucleotides together and a third nucleotide, and a fourth nucleotide, when you polymerize nucleotides together they get polymerized, the phosphate of one gets linked to the 3' carbon of another.

'碳部位重要是因为,当你把两个核苷酸聚合在一起,然后再聚合第三个,第四个的时候,核苷酸在聚合时,磷酸基与另外一个戊糖的3'碳部位连接

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