【单选题】Miss Li is _____ than Mr Cheng in our school. [ ]
【单选题】光电编码器在高速旋转测速中一般采用给定时间间隔T内对编码器的输出脉冲进行计数,这种方法测量的是_____,又称为M法测速
【简答题】动物细胞作为受体细胞进行外源基因的表达有何优点?
【多选题】动物细胞作为受体细胞的优点:
A.
能识别和除去外源真核基因中的内含子,剪切和加工成熟的mRNA。
B.
真核基因的表达蛋白在翻译后能被正确加工或修饰,产物具有较好的蛋白质免疫原性,约为酵母细胞的16~20倍。
C.
易被重组DNA质粒转染,具有遗传稳定性和可重复性。
D.
经转化的动物细胞可将表达产物分泌到培养基中,便于提纯和加工,成本低。
【单选题】Parents are advised to take pressure their chileren and give them some encouragement before an exam.
【简答题】动物细胞作为受体细胞进行外源基因的表达有何优点?
【简答题】Miss Cheng will never forget her first visit to Canada ,________?
【简答题】Some parents in China are sending their children to kindergartens to take foreign language courses; with a view to developing their kids foreign language skills, even though they have to pay up to 40,...
【单选题】Please take some _____ to your parents. [ ]
【单选题】Miss Cheng will never forget her first visit to Canada, ( )?