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【单选题】Passage Two In 1997, devotees of home electronics eagerly awaited the DVD player, a new device that could play movies without videotape, and with greater clarity. It caught on even faste...
A.
die economic realities of its practicality
B.
robust economic growth
C.
economic problems of hi-tech companies
D.
ignorance of the technology
【单选题】仅在真核细胞中存在而在原核细胞中不存在的细胞结构不包括以下那一项?
A.
Cell wall
B.
Ribosome
C.
Nucleus with membrane
D.
Organelles with membrane
【单选题】提取组织或细胞基因组DNA使用的蛋白酶K的作用是()
A.
破坏细胞膜、核膜
B.
使组织蛋白与DNA分离
C.
抑制DNase的活性
D.
降解蛋白质
E.
抑制RNase的活性