首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
To live forever was the dream of many emperors in ancient China. People was ordered to call them Wansui, which means 10 000 year
To live forever was the dream of many emperors in ancient China. People was ordered to call them Wansui, which means 10 000 year
admin
2013-01-28
28
问题
To live forever was the dream of many emperors in ancient China. People was ordered to call them Wansui, which means 10 000 years, but no human could live that long. How long can humans really live? According to the latest scientific discovery, humans are able to live up to the age of 120 or perhaps even longer.
Several recent studies showed that our life span can be extended far beyond normal limits. Cynthia Kenyon, a professor at the University of California in San Francisco, doubled the life of a worm from two weeks to a month. By changing the function of a single gene, known as daf-2, the scientist not only added extra days to the worm’s life but also kept it as healthy as worms which were half its age.
There are two similar genes in the bodies of mammals. By changing the function of one gene, scientists extended the life of a mouse by 18 per cent (or 4. 5 months). Another gene is called IGF-1. Researchers still don’t know how it affects our body. But by reducing its functions, the life of a mouse increases by 33 per cent (or 8. 6 months). The average life span of a mouse is 26 months.
In the experiment of extending life,
an ancient saying
, ’’you are what you eat," also seems to be true. Vegetables contain fewer calories than meat, and help to prolong life, scientists say. Research has found that taking in fewer calories affects our lives in a similar way to reducing IGF-1.
US biologist John Phelan suggests low calorie diets could increase human life span, but there is no proof yet.
Researchers are still waiting for the results of a study started in 1987. Monkeys are fed with low calorie food to see what happens. A monkey’s typical life span is 40 years, so there is a little while to wait.
In China, average life expectancy has now reached 70, double that of 1949. Increasing the length of our lives may bring us closer to the dreams of our ancient emperors. But it may also cause social problems such as housing and employment, social scientists have warned. (360 words)
After the function of IGF-1 is changed, about how long will a mouse live?
选项
A、26 months.
B、30 months.
C、18 months.
D、35 months.
答案
D
解析
老鼠的平均寿命是26个月,改变IGF一1基因功能多活8.6个月,这就是说它能活34.6个月,D“36个月”与之最接近。
转载请注明原文地址:https://kaotiyun.com/show/jk1O777K
0
考博英语
相关试题推荐
Universitiesarefrequentlyjudgedonthebasisoftheaccomplishmentsoftheirprofessorsandscientists.Scientistswhopublis
Itisstrictly_______thataccesstoconfidentialdocumentsisdeniedtoallbutafew.
Aschildrengetolder,self-disciplineshouldtaketheplaceofimposeddiscipline.Constrainsbecomeinternalizedandchildren
Aschildrengetolder,self-disciplineshouldtaketheplaceofimposeddiscipline.Constrainsbecomeinternalizedandchildren
Humanchoice,nottheintrinsiccontentofscience,determinestheoutcomeandscientists,ashumanbeings,thereforehaveaspe
She______hisinvitationtodinnerasshewasonadiet.
Themostnoticeabletrendamongtoday’smediacompaniesisverticalintegration--anattempttocontrolseveralrelatedaspectso
TheearlyretirementofexperiencedworkersisseriouslyharmingtheUSeconomy,accordingtoanewreportfromtheHudsonInsti
Weneedonehundredmoresignaturesbeforewetakethe______tothegovernor.
ClimaticconditionsaredelicatelyadjustedtothecompositionoftheEarth’satmosphere.Iftherewereachangeintheatmosphe
随机试题
Thoughdifferenteducationalsystemshavedifferentpurposes,onethingiscertain:allstudentsshouldtakepart【C1】________exa
布劳的著作是()
Notallmemoriesaresweet.Somepeoplespendalltheirlivestryingtoforgetbadexperiences.Violenceandtrafficaccidentsc
关于腺苷脱氨酶(ADA)缺陷的描述,正确的是
A.孤府B.玄府C.精明之府D.髓之府E.血之府汗孔的别称是
患者,男,48岁。平素嗜酒,近2周腹大坚满,脉络怒张,胁腹刺痛,面色黯黑,面颈胸臂有多个血痣,呈丝纹状,手掌赤痕,口渴不欲饮,舌质紫红,脉细涩。诊为
下面哪些不属于龙骨的功效
按装修材料的实际应用分类,吊顶材料属于()。
下列哪些机关单位的秘书工作机构可被称为“办公室”?()
有一部96集的电视剧从周三开始在某电台播放。正常情况下,周二至周五每天播放一集,周六、周日每天播放两集,周一停播。播完35集后,遇抗战纪念日专题报道,停播电视剧三天,之后继续按常规播放。那么该电视剧最后一集将在周几播出?
最新回复
(
0
)