反冲洗过滤罐是清洗罐内（）的重要措施。A.脏物 B.原油 C.积水 D.放射物 发布时间：2019-10-01 02:40 │ 来源：www.tikuol.com 题型：单项选择题 问题： 反冲洗过滤罐是清洗罐内（）的重要措施。A.脏物B.原油C.积水D.放射物
题型：单项选择题 实验室常用乳糖操纵子控制目的基因的表达，别乳糖作为诱导剂使用，它在乳糖操纵子启动表达中的作用是（）A.作为辅阻遏物结合于阻遏物与RNA聚合酶之间B.作为阻遏物结合于乳糖操纵子的操纵序列上C.使阻遏物变构而失去结合特异性DNA序列的能力D.是乳糖操纵子结构基因的表达产物E.是乳糖操纵子转录的产物 查看答案
题型：单项选择题 完形填空。 It was the night before the composition was due. As I looked at the list of topics, "The Art of EatingSpaghetti (意大利面条)" caught my eye. The word "spaghetti" brought back the 1 of an evening at Uncle Alien's in Belleville 2 all of us were seated around the table and Aunt Pat 3 spaghetti for supper. Spaghetti was an exotic (外来的) treat in 4 days. Never had I eaten spaghetti, and 5 of the grown-ups had enough experience to be 6 it. What laughing 7 we had about the 8 respectable method for moving spaghetti from plate to mouth. 9 , I wanted to write about that, but I wanted to 10 it down simply for my own 11 not for Mr. Fleagle, my composition teacher. 12 ,I would write something else. When I finished it the night was half gone and there was no 13 left to write a proper composition for Mr. Fleagle. There was no choice next morning but to 14 my work. Two days passed before Mr.Fleagle returned the 15 papers. He said, "Now, class, I want to read you a composition," "The Art of Eating Spaghetti". My words! He was reading my words out 16 to the whole class. 17 laughed, then the wholeclass was laughing with open-hearted enjoyment. I did my best not to show 18 , but what I was feelingwas pure happiness, 19 my words had the power to make people 20 . ( )1.A.memory ( )2.A.when ( )3.A.cooked ( )4.A.their ( )5.A.none ( )6.A.careful about ( )7.A.speeches ( )8.A.nearly ( )9.A.Especially ( )10.A.settle ( )11.A.work ( )12.A.However ( )13.A.time ( )14.A.give up ( )15.A.written ( )16.A.loud ( )17.A.People ( )18.A.shock ( )19.A.if ( )20.A.excited B.thought B.where B.served B.past B.one B.good at B.lessons B.naturally B.Probable B.put B.story B.Therefore B.excuse B.continue B.graded B.fast B.Nobody B.wonder B.for B.satisfied C.knowledge C.since C.got C.last C.any C.fond of C.sayings C.officially C.Suddenly C.bite C.luck C.As for him C.way C.hand in C.collected C.slowly C.Somebody C.worry C.while C.think D.experience D.after D.made D.those D.neither D.interested in D.arguments D.socially D.fortunately D.let D.joy D.Except for that D.idea D.delay D.signed D.calmly D.I D.pleasure D.although D.laugh 查看答案