原核生物mRNA()。
A、加工的第一步是甲基化
B、加工的第一步是切除多余核苷酸
C、加工的第一步是外显子对接
D、加工的第一步是在5’-端加上“帽子”结构
E、不需加工
参考答案:E
222. The gentleman made an apology for the mistake he had , for he had taken my suitcase _____ mistake the day before.
A.had; for
B.made; for
C.had; by
D.made; by
什么是汽轮发电机组的汽耗率?车间汽轮机的额定汽耗率是多少?