核糖核酸。
顺存在于生物细胞以及
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毒、类
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毒中的遗传信息载体。
RNA由核糖核苷酸经磷酯键缩合而成长链状
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子。一
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核糖核苷酸
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子由磷酸,核糖和碱基构成。RNA的碱基主要有4种,即A腺嘌呤,G鸟嘌呤,C胞
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,U
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。其中,U(
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)取代了DNA中的T胸腺
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而成为RNA的特征碱基。
与DNA不同,RNA一般为单链长
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子,不形成双螺旋结构,但是很多RNA也需要通过碱基配对原则形成一定的二级结构乃至三级结构来行使生物学功能。RNA的碱基配对规则基本和DNA相同,不过除了A-U、G-C
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