构成核酸的基本单位是()
A.磷酸戊糖
B.核苷
C.核苷酸
D.多核苷酸
E.脱氧核苷
参考答案:C
After months of voyage, Columbus arrived in________later proved a new continent. [ ]
A. where
B. what
C. which
D. that
当BSS收到DISC(断开帧)时,下列哪个定时器启动?()
A.rr_t3109
B.rr_t3110
C.rr_t3212
D.rr_t3111