Uracil -- a pyrimidine found in RNA that base-pares with adenine.

尿嘧啶--核糖核酸中的一种嘧啶，与腺嘌呤形成碱基对。

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The only difference is that in the RNA copy, thymine is replaced with the closely related base uracil, commonly abbreviated u.

唯一的区别在于，在RNA复制中，胸腺嘧啶被密切联系的、常被缩写为U的碱基尿嘧啶替换。

youdao

Uracil a nitrogenous base that is found in RNA but not in DNA.

存在于rna而非dna中的一种含氮碱基。

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