试题与答案

核糖体是进行蛋白质合成的重要细胞器,蛋白质在酸、碱或酶的作用下能发生水解反应生成

题型:选择题

题目:

核糖体是进行蛋白质合成的重要细胞器,蛋白质在酸、碱或酶的作用下能发生水解反应生成氨基酸,氨基酸分子中含有氨基(-NH2具有碱的性质)和羧基(-COOH,具有酸的性质)。氨基酸分子具有的性质是 [ ]

A.只能与硫酸反应,不能与氢氧化钠反应  

B.只能与氢氧化钠反应,不能与硫酸反应  

C.既能与硫酸反应,又能与氢氧化钠反应  

D.既不能与硫酸反应,又不能与氢氧化钠反应

答案:

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题型:阅读理解

What are you going to do if you are in a burning house? How will you escape? Do you know how to save yourself? Please read the following passage.

Escaping a fire is a serious matter. Knowing what to do during a fire can save you life. It is important to know the ways you can use and show them to everyone in the family, such as stairways and fire escapes, but not lifts.

  From the lower floors of the buildings, escaping through windows is possible, learn the best way of leaving by windows with the least chance of serious injury.

  The second floor window is usually not very high from the ground. An average person, hanging by the finger-tips will have a drop of about six feet to the ground. It is about the height of an average man. Of course, it is safer to jump a short way than to stay in a burning building.

  Windows are also useful when you are waiting for help. Be sure to keep the door closed. Or smoke and fire may be drawn into the room. Keep your head low at the window to be sure you get fresh air rather than smoke that may leaked(渗) into the room.

  On a second or third floor, the best windows for escape are those that open onto a roof. From the roof a person can drop to the ground more safely. Dropping onto cement(水泥) might end in injury. Bushes(灌木丛) and grass can help to break a fall.

小题1:It is important to _______.

A.put out the fire in the burning house

B.know the ways to escape the fire

C.jump off a burning house

D.keep the door closed小题2:It is possible to escape through the windows _______.

A.if there are some bushes on the ground

B.if you are strong enough

C.if you live on a lower floor

D.If you have a long rope小题3:Which of the following escaping way is NOT right? _______.

A.You can escape though stairways.

B.You can choose fire escapes.

C.Escape from the windows that open onto a roof.

D.Use a lift to come down at once.小题4:Open the window so that _______ if the building is on fire.

A.you can get fresh air

B.you can call for help

C.you can easily jump off

D.you can be seen first小题5:The best title of the passage is _______.

A.Escaping from the Windows

B.Save Yourself in the Burning House

C.Knowledge on Fire

D.Waiting for Help

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