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
Dolly the clone (克隆羊多利) was born a lamb, but her chromosomes (染色体) tell a differen story. They say she was already a few years o
Dolly the clone (克隆羊多利) was born a lamb, but her chromosomes (染色体) tell a differen story. They say she was already a few years o
admin
2012-07-18
50
问题
Dolly the clone (克隆羊多利) was born a lamb, but her chromosomes (染色体) tell a differen story. They say she was already a few years old by the time she left her mother’s womb.
Scientists at the Roslin Institute in Scotland finally took a close look at Dolly’s chromosomes and found that their ends, or telomeres(端粒—染色体端位上的着色点), are shorter than those of normal sheep of Dolly’s age. Telomeres, scientists think, are a major factor in aging—the shorter they are, the closer the cell is to dying.
The scientists also looked at the telomere length of two other sheep, one cloned from a 9-day-old embryonic cell(受孕的胚胎细胞) and the other from a 25-day -old fetal cell. The sheep cloned from the 9-day -old cell had the longest telomeres of the three, suggesting that the key factor in determining telomere length seems to be the number of divisions the cell undergoes before being cloned.
All three clones appear to be healthy, and whether the animals will have a shorter life span as a result of their shorter telomeres remains an open question. But the shortened telomeres do suggest that genetic blueprints may wear out over time, making it impossible to clone an animal endlessly.
Countless sheep can be cloned from one fetal cell.
选项
A、Right.
B、Wrong.
C、Doesn’t say.
答案
B
解析
见原文最后一句话。
转载请注明原文地址:https://kaotiyun.com/show/B2ld777K
本试题收录于:
公共英语一级笔试题库公共英语(PETS)分类
0
公共英语一级笔试
公共英语(PETS)
相关试题推荐
Mynineyearolddaughter,Maria,isinYearFour.Everyeveningwegetintohomeworkbattles(争执).Threeafternoonsaweek,she
情景:陈芳的妈妈因下雨路滑在上班途中骑自行车摔到,造成骨折。市第四中学高二学生何亮正巧路过,马上叫出租送她到医院,垫付车费并帮助联系家属。任务:请你用陈芳的名义写一封50字左右的感谢信给学校。请用下面的格式:DearPrincipal,Chen
Whenwillthesportsmeetingbegin?
Peoplebuythingsthere.Peopleuseittogoabroad.
A、 B、 C、 A图片是2008年北京奥运会的三种不同的吉祥物(mascot),属于考查常识。句中出现的是Huanhuan(欢欢),因此本题应选[A]。[B]是迎迎,[C]是贝贝。
Whydosomeanimalssleepinwintertime?Whatkeepthemliveinwinter?
Hobbswasanorphan(孤儿).Heworkedinafactoryandeverydayhegotalittlemoney.Hardworkmadehimthinandweak.Hewante
HebegantostudyEnglishsixyearsago.HehasstudiedEnglish______.
假如你是李林,因患感冒不能按时上课,需请假两天。请你使用下面所给词语,给Mr.Wang写一张请假条。(80个单词左右)参考词汇:haveabadcold,headache,coughtheday,seeadoctor,stayin
A、 B、 C、 B[A]是ClassThree,Gradeone,[B]是ClassOne,GradeTwo,[C]是ClassTwo,GradeThree,因此应选[B]。
随机试题
某市技术监督局根据举报,对同源公司进行突击检查,发现该公司正在超出许可范围生产,立即查封了厂房和设备,事后作出了没收全部超范围生产的产品并处罚款的决定。同源公司既不申请行政复议,也不提起行政诉讼,且逾期拒绝履行处罚决定。对于同源公司拒绝履行处罚决定的行为,
时间速度积分的单位是
围绝经期综合征的主要症状是
早孕的临床表现不包括
ABC会计师事务所负责审计D集团公司2014年度财务报表,并委派A注册会计师担任审计项目合伙人。D集团公司属于家电制造行业,共有4家全资子公司,各子公司的相关资料摘录如下。要求:针对确定的重要组成部分,简单说明A注册会计师执行工作的类型。
刘女士是一位抑郁症患者,近几个月来都不愿意出门,感觉自己精神很虚弱,对什么都不感兴趣。接案以后,社会工作者在介入的开始阶段比较注重发掘刘女士自己感兴趣的事情,增强刘女士的行动动力。当刘女士开始尝试做一些自己喜欢的事情后,社会工作者相应提供一些新的行动方法和
师生关系在教学层面上的特点是()。
检察院准备开展一次关于打击食品安全渎职犯罪的培训班。请你组织前期准备工作。【试题类型】组织管理
设f(x)=x(x+1)(x+2)…(x+n),则f’(0)=________。
Thatladytoldmeittook________________________(步行不到五分钟就可以到达附近的公共汽车站).
最新回复
(
0
)