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用15N标记含有200个碱基的DNA分子,其中有胞嘧啶60个,该DNA分子在14N的培养基中连续复制4次。下列有关判断不正确的是
- A.含有15N的DNA分子占1/8
- B.复制过程中需腺嘌呤脱氧核苷酸600个
- C.含有14N的DNA分子占7/8
- D.复制结果共产生16个DNA分子
下列关于运动的分解的说法中不正确的是( )
A.初速度不为零的匀加速直线运动,可以分解成一个匀速直线运动与一个初速为零的匀加速直线运动
B.一个在平面上的曲线运动可以分解成两个直线运动
C.沿斜面向上的运动可以分解为一个水平方向的运动和一个竖直向上的运动
D.可以将斜向下速度为 9 m/s的运动分解成两个速度分别为3 m/s和5 m/s的匀速运动
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下列关于高等动物的三大物质代谢的叙述不正确的是
- A.呼吸作用为三大物质的相互转化提供了原料
- B.细胞中必需氨基酸主要来自食物
- C.葡萄糖转变成氨基酸与氨基转换作用有关
- D.1 g脂肪氧化分解释放的能量是1 g糖元的2倍多,所以脂肪是主要的能源物质
某无色溶液中可能含有I-、NH、Cu2+、SO,向该溶液中加入少量溴水,溶液呈无色,则下列关于溶液组成的判断正确的是( )
①肯定不含I- ②肯定不含Cu2+ ③肯定含有SO
④可能含有I-
A.①③ B.①②③ C.③④ D.②③④
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听力(共三节,共30分)
第一节(共5小题;每小题1.5分,满分7.5分)
听下面5段对话。每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项。听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。
1.How much will the woman pay for the books?
A.$2.5.
B.4.5.
C.7.5.
2.What is the relationship between the two speakers?
A.Teacher and student.
B.Classmates.
C.Husband and wife.
3.What does the woman mean?
A.She won’t go to the concert tonight.
B.She wants to go to the concert alone.
C.She doesn’t think the concert interesting.
4.Which of the following is TRUE?
A.The woman is on a diet.
B.The woman is not on a diet.
C.The ice-cream doesn’t taste good.
5.What’s the weather like now?
A.Sunny and dry.
B.Freezing cold.
C.Hot and humid.
第二节(共10小题;每小题1.5分,满分15分)
听下面4段对话。每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项。听每段对话或独白前,你有时间阅读各个小题,每小题5秒钟;听完后,各小题给出5秒钟的作答时间。每段对话或独白读两遍。
听第6段材料,回答第6~7小题。
6.How will the woman most probably go to the Burns Park finally?
A.By taxi
B.On foot
C.By bus
7.How long will the woman probably go along Lincoln Street before she can see the Burns Park?
A.Half an hour
B.A few hours
C.Several minutes
听第7段材料,回答第8~9小题。
8.What does the woman want to buy?
A.A bag.
B.A pair of shoes.
C.A sweater.
9.How much does the woman spend at last?
A.54.
B.52.
C.50.
听第8段材料,回答第10~12小题。
10.What are the two speakers talking about?
A.Action adventure movies.
B.The man’s travel experiences.
C.The woman’s desire to be a writer.
11.Where does the conversation most probably take place?
A.In a classroom.
B.At a travel service.
C.In a newspaper office.
12.What is the probable relationship between the two speakers?
A.Traveler and writer.
B.Teacher and student.
C.Professor and reporter.
听第9段材料回答第13~15小题。
13.What does the man want to do?
A.To play basketball with friends after work.
B.To try out for the company basketball team.
C.To get in shape and compete in a cycling race.
14.What is the woman’s main concern about her husband?
A.His health condition.
B.He will become a fitness fan.
C.He spends too much time outside.
15.What does the woman advise about the man’s diet?
A.He should have less salt.
B.He should eat less fruit.
C.He should eat less fatty foods.
第三节(共5个小题,每小题1.5分,满分7.5分)
听一段对话或独白后, 在相应的横线上填入正确的单词。
People once(16)__________ it uneasy that computers would take over the world from man one day.
Already today, (17)__________ than forty years later, as computers are helping us to do more and more work in business and in our personal lives, we are faced with a lot of problems.People usually trust computers too much.In fact, they(18)__________ as if they did not know that wrong buttons may be pushed, or that a computer may sometimes do wrong.(19)__________, these would be no point in making a computer if you had to check all its answers, but we should also use our own “inner computer” and check the machine when we have the feeling that something has gone wrong.
Maybe each computer should come with the following(20)__________:for all the help this computer may provide, it should not take the place of basic thinking and reasoning skills.