The phosphate is linked to this carbon on the pentose, and notice that there is a number on this carbon, it's called - it's the 5' carbon.

磷酸基连接在戊糖的一个碳原子上,注意在这个碳上有个数字,它叫做5'碳

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The 5' carbon has a phosphate off of it and that phosphate is linked to the 3' carbon of the next one and they all have a base hanging off the side.

'碳的磷酸基,连接到下一个戊糖的3'碳部位,它们都有连接在一侧的碱基

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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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