证实DNA复制是半保留复制的是
A. M.Meselson和F.W Staid
B. Watson和Crick
C. Okazaki和Lesch
D. Kom和Temin
E. Waston和Mizufani
The hotel will be in a tight comer this year unless the newly launched project ______ miracle.
A. is working
B. works
C. will be working
D. worked
Jane has ______ smile.
A. such a friendly
B. a such friendly
C. friend
D. such friendly
催化真核生物转录生成mRNA的聚合酶是
A. 内含子
B. 多顺反子
C. RNA聚合酶Ⅱ
D. 原核RNA聚合酶口
E. 多聚A聚合酶