首页
登录
职称英语
Since the beginning of history, man has been attracted by the idea of living
Since the beginning of history, man has been attracted by the idea of living
游客
2024-01-17
16
管理
问题
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, though a very powerful one. Many people have wondered whether it would be possible to find a way to preserve human bodies, and what would be the best way to preserve human bodies.
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, and in fact many people have explored this possibility.
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 are not only larger than the volume of the water originally in the cells, but also form sharp cutting shapes that harms 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 the damage, Luyet suggested removing some or all of the water from the cells before freezing them.
Using living cells from 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), a clear, thick liquid made chiefly from fats and oils. 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 very much 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. [br] The passage is mainly about______.
选项
A、the possibility of preserving human bodies by freezing
B、the practice of preserving food by freezing
C、the harmful effects of freezing
D、how to remove water from living cells
答案
A
解析
本题为中心主旨题。根据定位句,idea的内容live forever(长生不老)与A项(保存人类身体)最接近,故选A。
转载请注明原文地址:https://tihaiku.com/zcyy/3370383.html
相关试题推荐
Fromtheverybeginning,waterhasfurnishedmanwithasourceoffoodanda
Fromtheverybeginning,waterhasfurnishedmanwithasourceoffoodanda
Fromtheverybeginning,waterhasfurnishedmanwithasourceoffoodanda
Fromtheverybeginning,waterhasfurnishedmanwithasourceoffoodanda
Fromtheverybeginning,waterhasfurnishedmanwithasourceoffoodanda
Fromtheverybeginning,waterhasfurnishedmanwithasourceoffoodanda
Hefounditincreasinglydifficulttoread,______hiseyesightwasbeginningto
Livingthingsare______cells,andcellsdonotgrowtomorethantwicethesize
LivinginthecentralAmericandeserthasitsproblems,______obtainingwateris
(79)Inwhatnowseemsliketheprehistorictimesofcomputerhistory,theea
随机试题
[originaltext]Facialexpressionscarrymeaningthatisdeterminedbysituati
这时,潮水越来越大了,天边要根银色的线条,一会儿变成黑色,一会儿又普通成白色,渐渐地排山倒海般由远向近而来。由于夜静,这潮水确实比白天的大,真如千军万马,两
Researchershaveestablishedthatwhenpeoplearementallyengaged,biochem
Thereare17kindsofpenguinsintheworld.Allofthemliveinthesouther
TheAbortionClinicShootings:Why?A)Asthenationheardwith
异烟肼抗结核杆菌的机制是()A:抑制细菌细胞壁的合成 B:影响细菌膜的通透性
正常成人在清醒、安静和闭眼放松情况下,ECG枕部和顶部主要为:()A.α
根据FIDIC《土木工程施工合同条件》,关于履约担保的说法正确的有( )A.
各种运输方式内外部的各个方面的构成和联系,就是( )。 A.运输系统
军休社会工作服务对象的需要包括()。A.军队情结 B.社会尊重 C.健康维
最新回复
(
0
)