决定氨基酸的密码子指()
A.DNA上的3个相邻的碱基;
B.tRNA上的3个相邻的碱基;
C.mRNA上的3个相邻的碱基;
D.基因上的3个相邻的碱基。
参考答案:C
以销售商品,提供劳务为主营业务的企业,销售单独计价的包装物实现的收入通过“主营业务收入”科目进行核算。( )
—Did they clean the house yesterday afternoon?
—______. They cleaned it this morning.
A.No, they don’t
B.Yes, they did
C.No, they didn’t
D.Yes, they do