题目内容
Since the beginning of history, man has been attracted by the idea of living forever, of winning the fight against death and disease. So far, this has only remained a dream. Many people have wondered whether it would be possible to find a way to preserve human bodies, and what would be the best way.
It has long been known that meat of fruit can be kept fresh for long periods by freezing; in ancient China, for example, food was stored with ice to keep it fresh. This method could also be useful for preserving humans.
However, most living beings that exist under warm conditions die when frozen. This is because of the harmful effects of freezing ice crystals(晶体), which not only are larger than the volume(体积) of the water originally in the cells, but also form sharp cutting shapes that harm the cells.
In the 1940s Dr B.J. Luyet and a group of scientists in England were working on the problem of freezing cells without damaging them. Since the harm caused by ice crystals was the main cause of damage, Luyet suggested removing some or all of the water from the cells before freezing them.
Using living cells form chicken, Luyet and his assistants discovered that they could partly dry the chicken cells, using a mixture of the white part of an egg and glycerin (丙三醇). Some success was obtained. The chicken cells were dried, frozen for a period of time, and then carefully unfrozen. Almost all the cells recovered when they reached normal temperatures.
Since then, the cooling of whole animals to a temperature far below freezing point for later unfreezing has become more of a possibility, and the glycerin method would probably be used to accomplish this. When this can be done completely and successfully, science will have moved much closer to its aim of freezing and storing incurable patients until the day they can be cured.
【小题1】What does the passage mainly talk about?
A.Easy but practical ways to remove water from living cells. |
B.The possibility of preserving human bodies by freezing. |
C.The practice of preserving food by freezing. |
D.The harmful effects of freezing. |
A.has already been realized |
B.was invented in ancient China |
C.has its roots in the way of storing food |
D.is widely accepted by the scientific world |
A.is harmful to living cells |
B.is the best way of preserving food |
C.reduces the volume of water in living cells |
D.is a way of removing water from living cells |
A.It is impossible to have whole animals frozen. |
B.It remains unknown how to unfreeze frozen animals. |
C.Freezing incurable patients for later treatment is still an idea. |
D.The glycerin method has already been adopted to treat patients. |
【小题1】B
【小题2】C
【小题3】A
【小题4】C
解析试题分析:这篇文章讲的是通过冷冻的方法保存人类身体的可能性。因为冷冻对活的细胞是有害的,科学家用glycerin方法解决了这个问题,这个方法可用于冷冻不可治愈的病人供以后治疗。
【小题1】主旨题:从第一段的句子:Many people have wondered whether it would be possible to find a way to preserve human bodies, and what would be the best way. 可知这篇文章讲的是通过冷冻的方法保存人类身体的可能性。选B
【小题2】细节题:从第二段的句子:It has long been known that meat of fruit can be kept fresh for long periods by freezing; in ancient China, for example, food was stored with ice to keep it fresh. This method could also be useful for preserving humans. 可知冷冻保存人类身体的办法是来自于保存食品。选C
【小题3】细节题:从第三段的句子:This is because of the harmful effects of freezing ice crystals(晶体), which not only are larger than the volume(体积) of the water originally in the cells, but also form sharp cutting shapes that harm the cells 可知冷冻对活的细胞是有害的,选A
【小题4】细节题:从最后一段的句子:When this can be done completely and successfully, science will have moved much closer to its aim of freezing and storing incurable patients until the day they can be cured. 可知冷冻不可治愈的病人供以后治疗还是一个想法。选C
考点:考查科普类短文
点评:这篇文章讲的是通过冷冻的方法保存人类身体的可能性。这篇阅读理解集中考查了细节理解题,要求考生仔细阅读全文,做好相应的标志,以提高阅读的效率和速度,做题时要审清题干,发觉和把握试题中有效的提示性信息,确认命题的角度、阅读范围和答题方式。
My colleague has been recovering gradually since the operation, and it wont’ be long ______ he comes back to work.
A.before |
B.since |
C.after |
D.when |