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【单选题】
下列关于基因工程的叙述,错误的是 ( ) A .目的基因和受体细胞均可来自动、植物或微生物 B .限制性核酸内切酶和 DNA 连接酶是两类常用的工具酶 C .人胰岛素原基因在大肠杆菌中表达的胰岛素原无生物活性 D .载体上的抗性基因有利于筛选含重组 DNA 的细胞和促进目的基因的表达A.
B.
C.
D.
D
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【简答题】重装 Windows Server 2008 后,原来加密的文件为什么无法打开?
【单选题】—Can you tell me anything about the fire ______ last night? —I'm afraid, ______
A.
taking place, a little
B.
that broke out, very little
C.
broke out, just a little
D.
happened, quite a few
【单选题】母牛1~2d内表现兴奋不安、大声嗷叫、追逐或趴跨其他牛,阴唇略有充血水肿,阴道内有透明黏性很强的黏液排出,直肠检查卵巢上有1~2个表面光滑、壁紧张、有波动感、18~20mm的小泡状物,略突出于卵巢表面,这极可能是( )。
A.
持久黄体
B.
黄体囊肿
C.
正常发情卵泡
D.
卵泡囊肿
【单选题】At last all the enemy was _______ by the PLA. [ ] A. passed away
B.
killed out
C.
wiped out
D.
set up
【单选题】The PLA are now searching for a woman who is reported to______ since the quake hit the area last Monday. [ ]
A.
have been missing
B.
have got lost
C.
being missing
D.
get lost
【单选题】列关于动物临床三大指标的描述，正确的是（）
A.
正常时，奶牛体温为37.5～39.5℃，呼吸频率为10～30次/min，脉搏频率为50～80次/min
B.
正常时，水牛体温为37.5～38.5℃，呼吸频率为10～30次/min，脉搏频率为30～50次/min
C.
正常时，猪体温为38～39.5℃，呼吸频率为18～30次/min，脉搏频率为60～80次/min
D.
正常时，犬体温为37.5～39℃，呼吸频率为10～30次/min，脉搏频率为60～90次/min
E.
正常时，羊体温为38～40℃，呼吸频率为20～30次/min，脉搏频率为70～80次/min
【简答题】SQL语句中删除一个表中记录,使用的关键字是( )。
【单选题】The mayor is happy to find that many trees _______ in our city last year.
A.
plant
B.
were planted
C.
planted
D.
are planted
【单选题】— Your city looks beautiful! —Yes. Lots of trees and grass ____ last year. [ ]
A.
are planted
B.
have planted
C.
were planting
D.
were planted
【简答题】选出你所听到的句子。 ( )1．A．We played sports last weekend. B．We played tennis last weekend. C．We played the guitar last weekend. ( )2．A．June went to the pool last Sunday morning. B．June didn't go to the...
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