首页
登录
职称英语
Henry III didn’t know much about biology. He went through six wives back in
Henry III didn’t know much about biology. He went through six wives back in
游客
2024-01-26
4
管理
问题
Henry III didn’t know much about biology. He went through six wives back in the 1500s, looking for one who could bear him a son. Scientists now know that it’s the father’s sperm, not the mother’s egg, which determines whether a baby is a boy or a girl. And last week researchers at the Genetics and IVF Institute, a private fertility (生育能力) center in Virginia, announced a new technique that will allow parents to choose the sex of their baby-to-be, before it has even been conceived. The scientist used a tiny laser detector to measure the DNA in millions of sperm cells as they pass single file through a narrow tube, like cattle being herded through a corral (牲口栏). In a study published last week, "girl sperm," which has more DNA—the genetic material—in each cell, was collected, while "boy sperm" was discarded. And when purified girl sperm was used to impregnate (使受孕) a group of mothers, 15 of 17 resulting babies turned out to be girls.
The researchers say that "sex selection" can also double a mother’s chance of having a son and can be used to avoid genetic diseases that affect only one gender, such as hemophilia (血友病). But some experts, like New York University fertility specialist Dr. Jamie Grifo, worry that sex selection could lead to a kind of in uteri (子宫) discrimination, especially in cultures where sons are considered superior to daughters. "It’s valuing one gender over another," Grifo says. "I don’t think that’s something we should be doing." So far, patients at the institute have been asking for both boys and girls, in order to "balance" their families. And some ethics experts say that’s fine, as long as parents are just looking for a little gender variety. "If you have three boys, and you want a girl," says University of Texas reproductive-law professor John Robertson, "that’s not gender bias at all." [br] The DNAin the sperm cells can be measured _____.
选项
A、in the same way how the cattle are herded
B、when they pass through a tube one behind the other
C、after they pass through a laser tube
D、when they are scanned by a laser detector all at a time
答案
B
解析
推理判断题。解答本题的关键在于堆断single file的意思。该句把精子通过试管的情形与牛群被赶入牲口圈的情形作对比,结合single一词本身的意思,可以推断single file是“一个接一个”的意思,只有选项B能表达这个意思,由此也可否定选项D。选项A最具干扰性,原句是把精子通过试管的情形比作牛群被赶入牲口圈的情形,而选项A说的是测定精子内DNA的方法与放牧的方法相同,显然选项A只是引用了原文的某些词语,但表达的意思与原文却截然不同。
转载请注明原文地址:https://www.tihaiku.com/zcyy/3396291.html
相关试题推荐
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
Accordingtoarecentstudy,theideaofagingmightlookdifferentthrought
HenryIIIdidn’tknowmuchaboutbiology.Hewentthroughsixwivesbackin
HenryIIIdidn’tknowmuchaboutbiology.Hewentthroughsixwivesbackin
随机试题
[originaltext]W:Itseemssomethingisweighingonyourmindthesedays.What’s
27岁初产妇,宫口开大5cm,诊断为持续性枕后位,s=0,胎心168次/分。本例
阅读下列说明,回答问题1至问题3,将解答填入答题纸的对应栏内。【说明】某市信息资
下列关于楼梯构造叙述不正确的有()。A:当荷载或梯段跨度较大时,采用梁式楼梯比
A.保和丸加减 B.柴胡疏肝散加减 C.霍香正气散加减 D.香砂六君子汤加
某系统性红斑狼疮的女患者,病史两年,有发热和关节肿痛,面部发现紫红色斑块并有少量
化生"涎"的脏腑是A、肾 B、肺 C、脾 D、肝
在证券回购交易中,融资方应确保在登记结算机构保留存放的标准券的数量应()融入资金
资料:Whatattractscustomers?Obviouslyth
某市新建污水处理厂,其中二次沉淀池采用圆形(直径16m)整体式现浇无粘结预应力
最新回复
(
0
)