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
Researchers have reconstructed an ancient human genome(基因组)for the first time, thanks to the discovery of a 4000-year-old strand
Researchers have reconstructed an ancient human genome(基因组)for the first time, thanks to the discovery of a 4000-year-old strand
admin
2016-08-29
66
问题
Researchers have reconstructed an ancient human genome(基因组)for the first time, thanks to the discovery of a 4000-year-old strand of hair in Greenland permafrost(永冻土). Experts say that similar techniques could be employed in many other ways, such as analyzing the DNA of South American mummies or crime victims.
The sample was taken from one of four strands of hair collected in Greenland by Danish archaeologists in the 1980s. The hairs are the only known human remains from the earliest people to settle in Greenland. A chance conversation alerted University of Copenhagen researcher Eske Willerslev, who was just back from two unsuccessful months in Greenland searching for human remains to test for DNA, to the sample, which had been stored at the National Museum of Denmark for more than 20 years.
Once they had the hairs in their possession, Willerslev and colleagues set about sequencing the sample. The team used dozens of sequencing machines to identify and map DNA fragments in the hair shafts, a process that took nearly 2 months. The data revealed more than 80% of the genome, coverage comparable to what can be done with a modem human genome.
"From the DNA, we can tell a lot about the individual," says Willerslev. "He had brown eyes, brown skin, a tendency to baldness, and dry earwax." The researchers have named him "Inuk," which means "man" or "human" in Greenlandic.
The genome also sheds light on where the man’s relatives came from. When the researchers compared his DNA with that collected from more than 40 Arctic and native North American populations, they concluded that the first people to settle in Greenland were related to groups now living in northeastern Siberia. The analysis also revealed that these first colonists were not the ancestors of the Inuit who live on the island now.
The researchers say that when it comes to ancient DNA, the Greenland sample may amount to low-hanging fruit. The hair had been preserved by cold for thousands of years, ideal conditions for recovering DNA "Working with these young permafrost samples is worlds apart from working with older, non-permafrost samples," says Adrian Briggs, a researcher at the Max Planck Institute. He notes that the Greenland sample contains tens of thousands of times more DNA than typically found in Neandertal and early modem human samples from warmer environments.
Yet the discovery shows that with ever-cheaper genetic sequencing and faster computers, it is possible to recover a full nuclear DNA sequence from an ancient human, even when the genome is broken into tiny fragments. The nicest thing this paper shows is that the application of next-generation sequencing techniques is really going to expand what we can do with ancient DNA.
What do we know about "Inuk"?
选项
A、It signifies where the ancient man was found.
B、It represents where the ancient man was born.
C、It comes from a language spoken in Greenland.
D、It describes the ancient man’s physical features.
答案
C
解析
原文该句末尾的定语从句表明了“Inuk”这个名字的命名原因,其中的in Greenlandic表明Greenlandic应为一个名词,根据从句的结构可以推断Greenlandic最可能是“格陵兰语”的意思,因此,本题应选C。
转载请注明原文地址:https://kaotiyun.com/show/eYG7777K
0
大学英语六级
相关试题推荐
ItisnoteasytotalkabouttheroleofthemassmediainthisoverwhelminglysignificantphaseinEuropeanhistory.Historyan
A、Checkyournumberandcallagain.B、Telltheoperatorwhathashappened.C、Asktheoperatortoputyouthrough.D、Asktheoper
A、Manyprogramsareprovided.B、Itisdifficulttogetin.C、Students’feesareratherhigh.D、Studentshavemanychancestogo
A、Itcombinesdifferentfeelingstogether.B、Itcanexpresssomeveryconfusingfeelings.C、Itexaggeratessomespecialfeelings
A、Theairiscontaminated.B、Peoplethereareexhausted.C、It’stoowindyforswimming.D、Thebeachesaredirty.ABUT题。But后面的转折
A、Fantasticsettings.B、Specialeffects.C、Mysteriouscostumes.D、Mysteriousweapons.B
It’sTimetoPayAttentiontoSleep,theNewHealthFrontier[A]Yourdoctorcouldsoonbeprescribingcrucialsleepastreatment
Manynewmotherssufferfromextremetirednessevenfourmonthsaftergivingbirth,promptingexpertstowarntheyshouldnothu
A、Listentotheradioreport.B、GetoffRoute27.C、Changetheradiostation.D、Stopworryingabouttheweather.A“snowstorm”是指“
IntheBritishMuseumonaSundayafternoon,ancientfaceslookbackatchildrenandadultsalike.Insidetheirglasscases,pha
随机试题
()直接引起无意注意。
七情影响脏腑气机,恐则
患者,男,46岁。腹痛腹泻2天,日泻10余次水便,经治已缓,目前口渴心烦,皮肤干瘪,眼窝凹陷,舌淡白苔薄黄,脉细无力。其证候是
社会主义法与社会主义道德的关系是()
甲花4万元收买被拐卖妇女周某做智障儿子的妻子,周某不从,伺机逃走。甲为避免人财两空,以3万元将周某出卖。(事实一)乙收买周某,欲与周某成为夫妻,周某不从,乙多次暴力强行与周某发生性关系。(事实二)不久,周某谎称怀孕要去医院检查,乙信以为
目前拥有世界上成交量最大的黄金期货合约的交易所是()。
阅读材料并回答问题。问题:从表中可以看出哪些行业国有化程度相对较高?
甲、乙两人从不同的地方出发,相向而行,甲的速度是乙的速度的1/5,乙的速度为20千米/小时,那么甲、乙两人相遇需要多少时间?(两个地方之间相距120千米)。
Sometimeinthenextcentury,thefamiliarearly-newspaperonthefrontgatewilldisappear.Andinsteadofreadingyournewspap
Everyyearthousandsofpeoplearearrestedandtakentocourtforshop-lifting.InBritainalone,aboutHK$3,000,000’swortho
最新回复
(
0
)