题目内容

在减数分裂Ⅰ的前期中染色体出现配对及交叉互换，此现象：


  1. A.
    发生在姊妹染色体之间
  2. B.
    发生在同源染色体之间
  3. C.
    在染色体之间随机进行
  4. D.
    在姊妹染色体之间与同源染色体之间均能发生
B
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Last year, I spent too much time ______ video game and I decided to quit it.


  1. A.
    in
  2. B.
    on
  3. C.
    with
  4. D.
    from

---Mr Hu, can you tell us how to learn math well?

---Sure. But remember nothing can be learned _________ hard work.


  1. A.
    by
  2. B.
    at
  3. C.
    without
  4. D.
    for

---Mr Hu, can you tell us how to learn math well?
---Sure. But remember nothing can be learned ______ hard work.


  1. A.
    by
  2. B.
    at
  3. C.
    without
  4. D.
    for

有一种人类中罕见的常染色体显性致病基因导致的疾病，在某海岛的人群中有很高的发病率。人类遗传学家在探讨该先天性疾病的高发病率成因时可能涉及到如下的哪种因素：


  1. A.
    该基因的突变率很高
  2. B.
    该海岛可能曾经发生过导致人类灾难的事件
  3. C.
    最初开发该海岛的少数移民
  4. D.
    该基因不受自然选择的作用

年年洄游到长江中上游产卵的一种国家一级保护动物是


  1. A.
    鲤鱼
  2. B.
    中华鲟
  3. C.
    桃花鱼
  4. D.
    娃娃鱼

形成蒴果的雌蕊具有的胎座类型是：


  1. A.
    边缘胎座、中轴胎座与特立中央胎座
  2. B.
    顶生胎座、侧膜胎座与特立中央胎座
  3. C.
    中轴胎座、特立中央胎座与侧膜胎座
  4. D.
    边缘胎座、侧膜胎座与基生胎座

从物质循环的观点来看，动物体中碳元素的最终来源是


  1. A.
    糖类中含有的碳
  2. B.
    大气中的二氧化碳
  3. C.
    蛋白质中含有的碳
  4. D.
    岩石中的碳
录音中有10组对话,每组对话听两遍,然后从每小题A、B、C中选出能回答所给问题的正确答案。
1. Who cooked dinner?
A. Jim.
B. Maria.
C. Maria's parents.
2. What does the man want to learn?
A. How to drive a car.
B. How to use a computer.
C. How to make a telephone call.
3. What did Fred use to do?
A. Swim.
B. Watch TV.
C. See movies.
4. What's the best movie theater?
A. Town Cinema.
B. Screen City.
C. Movie Palace.
5. What does John want to add in his coffee?
A. Some juice.
B. Some milk.
C. Some sugar.
6. Where was the man?
A. In a meeting room
B. In the hotel
C. In the reading room
7. Who is quieter, Tom or his brother?
A. Tom.
B. His brother.
C. They are both quiet.
8. What's Li Lei's sister going to be?
A. A computer programmer.
B. An engineer.
C. A pilot.
9. What does Toby's father like to best?
A. Sandwiches.
B. Noodles.
C. Dumplings.
10. How does Mary go to school?
A. By bike.
B. On foot.
C. By car.

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