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
23
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]W:Themusicandtheflowersarelovely.M:Yes.Ihopethatthe
TenTipsforSavingMoneyinCollegeA)Collegecanbean
WheredoestheTropicalstormmakelandfall?[originaltext](21)Tropicalstor
[originaltext]About20,000whaleshavebeenslaughteredsinceabanoncomm
工程建设合同纠纷的仲裁由(请作答此空)的仲裁委员会仲裁。仲裁委员会做出裁决以
狭义的咀嚼肌是指A.颞肌、下颌舌骨肌、翼内肌、翼外肌 B.二腹肌、咬肌、翼内肌
陈鹤琴先生认为,幼稚园课程的实施是实现教育目标的关键。在他的课程实施中主要采用(
教师在书写板书时要求尽量用白色粉笔,所依据的感知规律是()。 A.强度律 B
持手有成本理论的基本假设主要有()。A.借贷利率相同且保待不变 B.无税收和
下列哪项对病毒性肺炎无早期诊断价值 A.病毒分离 B.X线检査 C.特异性
最新回复
(
0
)