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
2023-06-28
33
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 gender of the baby is decided by_____.
选项
A、the father’s DNA
B、the mother’s DNA
C、the father’s sperm
D、the mother’s egg
答案
C
解析
事实细节题。第1段第3句which引导的非限制性定语从句修饰的是the father’s sperm,而不是插入语the mother’s egg,因此选项Ct确。
转载请注明原文地址:https://tihaiku.com/zcyy/2789003.html
相关试题推荐
Sixyearsago,aMiamiwomanwalkingthroughthehallofanofficebuilding
Sixyearsago,aMiamiwomanwalkingthroughthehallofanofficebuilding
Sixyearsago,aMiamiwomanwalkingthroughthehallofanofficebuilding
HenryIIIdidn’tknowmuchaboutbiology.Hewentthroughsixwivesbackin
HenryIIIdidn’tknowmuchaboutbiology.Hewentthroughsixwivesbackin
OlderAmericansareheadingintoandthroughretirementwithaboatload(船的载货
OlderAmericansareheadingintoandthroughretirementwithaboatload(船的载货
[originaltext]Literatureprovidesalensthroughwhichreaderslookatthe
[originaltext]Literatureprovidesalensthroughwhichreaderslookatthe
Whenyourunyourhandsthroughyourlover’shair,you’reprobablynotthink
随机试题
Forthispart,youareallowed30minutestowriteacompositionentitledAbi
Noonecanbeagreatthinkerwhodoesnotrealizethatasathinkeritis
SoonafterstartinghisjobassupervisoroftheMemphis,Tenn.,publicscho
三七能抗血小板聚集,抑制血栓形成,作用较强的有效成分是()。A.三七黄酮B.三
培养下列哪种细菌适合采用吕氏血清斜面培养基、尿素蛋黄双糖琼脂培养基()A.分离
下列方法中哪个不常用于吩噻嗪类药物的含量测定A.非水碱量法B.铈量法C.钯离子比
57、加强对运行、检修人员防误操作培训()应定期对运行、检修人员进行培训工作
描写过年习俗的古诗“千门万户曈曈日,总把新桃换旧符”中,“新桃”指的是()。A
A.纯化水 B.制药用水 C.注射用水 D.灭菌蒸馏水 E.灭菌注射用水
(2021年真题)某农户2021年2月经批准占用耕地1000平方米,900平方米
最新回复
(
0
)