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
2024-02-17
16
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] Girl sperm was preferred to boy sperm in the research most probably because______.
选项
A、girl sperm contains more genetic material
B、more mothers want to have girl babies
C、girl sperm is healthier and more active
D、girl sperm is more easily purified
答案
A
解析
事实细节题。第1段倒数第2句中的由which引导的定语从句表明选项A的叙述正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3459943.html
相关试题推荐
Japanisgoingthroughacomplexnationalidentitycrisis.Thatmaybenoba
Japanisgoingthroughacomplexnationalidentitycrisis.Thatmaybenoba
Hadheworkedharder,______(他就通过考试了).hewouldhavegotthroughtheexams“通过考试”用g
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthe
随机试题
Peanutsareoneoftheworld’smostnutritiousfoods.Peanutscontainp
K.C.couldrecallsomesentenceswithoutrememberinghehadtakensuchlessonsb
党的十九大报告指出,必须多谋民生之利、多解民生之忧,在发展中补齐民生短板、促进社
Thebeautyofsoftwareisinitsfunctio
颈静脉怒张不会出现在A.左心功能不全 B.右心功能不全 C.缩窄性心包炎
(2017年真题)评估人员拟采用市场提取法求取不动产的资本化率,收集到市场上近期
有关淤血性肝硬化,哪项说法不正确A.常由右心功能衰竭引起 B.Budd-Chi
企业通过效率评估,( ),从而找出差距和改进措施,进一步提高培训质量。A.与以
癃闭而有小腹胀满,口渴欲饮,咽干,呼吸短促,苔薄黄,脉数者。治宜选用A.八正散
居民个人一般通过()形式间接将资金注入市场。A.基金 B.资产管理计划
最新回复
(
0
)