首页
登录
职称英语
Women live longer than men because they are spoiled for choice. That is the
Women live longer than men because they are spoiled for choice. That is the
游客
2023-07-26
13
管理
问题
Women live longer than men because they are spoiled for choice. That is the startling conclusion of an international group of scientists who say they have found the cause of female longevity.
They say females have two separate cell lines in their bodies, while men have only one. Women in old age can "choose" the more robust (强壮的) of these lines and survive for many more years.
Why there should be such a persistent cross-cultural gap between the life spans of the sexes has baffled scientists until now. In a paper in the journal Blood, and reported in the current issue of New Scientist, researchers at Odense University in Denmark and Ulleval University Hospital in Norway point to a key difference in the sex-determining chromosomes (染色体) found in the cells of men and women.
Every cell in a woman’s body has two X chromosomes, one inherited from her mother and the other from her father. In each cell, one of these two X chromosomes is switched off. This means that a woman is a mosaic (混合体) of two cell lines: one derived from her father’s X chromosome, the other from her mother’s. By contrast, every cell in a man’s body has an X and a Y chromosome, neither of which is turned off. He has only one cell line. This difference could be crucial in determining the long-term health of men and women, scientists concluded, and so they decided to examine cells taken from young women.
They found an even division between their two different lines. However, when they looked at elderly females they found their bodies now favoured one set of cells at the expense of the other line. "This suggests that one of the cell lines is ’better’ than the other," say the researchers. In other words, women’s bodies may select the more vigorous of the two cell lines and allow it to predominate the twilight of their years, giving them a crucial advantage over men, who have no chance of choosing the healthier of two sets of cells. [br] "The twilight of their years" (Line 5, Para. 5) refer to______.
选项
A、their old years
B、their young years
C、their good years
D、their bad years
答案
A
解析
转载请注明原文地址:https://tihaiku.com/zcyy/2870975.html
相关试题推荐
Mostpeoplethinkcancerisadiseaseofrichwesterncountries.Nolongeri
Mostpeoplethinkcancerisadiseaseofrichwesterncountries.Nolongeri
Mostpeoplethinkcancerisadiseaseofrichwesterncountries.Nolongeri
Theyspendalotoftimetogetherbecausethey____________(有许多共同之处).havemuchi
Becausehedidn’tpayfortherent,_______________________(房东把他从公寓里赶了出去).thela
IfIwereyou,Iwouldn’t_____________(容忍他的行为)anylonger.putupwithhisbeha
[originaltext]W:Maybeyoushouldstudycommercialartbecausethat’salittle
[originaltext]W:Maybeyoushouldstudycommercialartbecausethat’salittle
[originaltext]W:Maybeyoushouldstudycommercialartbecausethat’salittle
Sendingachildtoanurseryatanearlyageisemotionallyharmful,becausethe
随机试题
WhydidMourinholeaveChelseaclub?[originaltext]AChelseafootballcluboffic
Eleven-year-oldAngelawasstrickenwithadebilitating(衰弱的)diseaseinvol
Whydoweinvestsomuchhopeinnewtechnologyandwhyarewesodisappoint
D
“忧者见之则忧,喜者见之则喜”这是受一个人的________影响所致:A.激情
根据《外商投资准入特别管理措施(负面清单)》(2019年版)的规定,不考虑其他因
下列有关封闭式和开放式基金的区别,正确的是( )。 ①存续期间不同 ②基金
某高层建筑,地上16层,层高4m,一至六层为商场营业厅,七层及以上为住宅,商场
访花的使者中,蝴蝶可就没有蜜蜂那种“老黄牛”精神了。看它飞东飞西,吃花粉却不生
A.川贝止咳露 B.养阴清肺膏 C.通宣理肺丸 D.苏子降气丸 E.降气
最新回复
(
0
)