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
考研
Now that we are fairly sure that there are many Earth-like planets in the Galaxy, the time is ripe (or almost so) to wonder whet
Now that we are fairly sure that there are many Earth-like planets in the Galaxy, the time is ripe (or almost so) to wonder whet
admin
2017-08-11
74
问题
Now that we are fairly sure that there are many Earth-like planets in the Galaxy, the time is ripe (or almost so) to wonder whether these new worlds do indeed have a high probability of hosting new forms of life.
Currently, the best【C1】______on the existence of other planets comes from NASA’s【C2】______Kepler satellite, which has been mapping an area of the sky【C3】______some 150,000 stars.
Scientists estimate that around 5 percent of planets in our galaxy have masses similar【C4】______Earth’s and, possibly, are within the habitable zone of their stars, meaning that【C5】______they hold water it has a high chance of being liquid.【C6】______there are about 200 billion stars in our galaxy alone, scientists estimate that there should be about 10 billion Earth-size planets. Not bad, especially if we【C7】______that to be Earth-size and within a habitable zone is all it takes for life to take hold in an【C8】______world. In practice, however, the situation is much more【C9】______, since it depends on what life is and how it appears in a planet,【C10】______on the planet’s detailed geological history.
Here on Earth life appeared some 3.5 billion years ago.【C11】______that it may have been here as far【C12】______as 3.8 billion years ago remain tentative. For about the first three billion years, life on earth was【C13】______in the form of single-cell creatures. Only when Earth’s atmosphere was full of oxygen did more sophisticated organisms appear.
【C14】______its unusual atmosphere, Earth’s heavy, single moon, its magnetic field also did something else that allowed complex life to【C15】______on its surface.【C16】______these, Complex life would find it very hard to【C17】______and survive.
The results from Kepler’s mission are encouraging and exciting. We have the【C18】______of confirming the existence of countless other worlds out there. Based on these findings, we should indeed【C19】______that other worlds would host some kind of simple life. However, as some scientists argued, Earth and its ability to host complex life will probably remain a【C20】______phenomenon in this and other galaxies.
【C17】
选项
A、evolve
B、persist
C、degenerate
D、ripen
答案
A
解析
上段中提到在量初的30亿年里,地球上的生命体基本是单细胞。直到大气层中充满氧气才出现更复杂的生物体。这是一个逐渐进化的过程,A项evolve“进化”符合要求。能和其后的survive“生存”构成语义并列。
转载请注明原文地址:https://kaotiyun.com/show/rcbZ777K
0
考研英语一
相关试题推荐
Ittakesawholegalaxyofthingstomakeyouhappy.Happinessisastateyoufeelwhenyouhavenoproblems,worries,doubtsor
"Always"."Never".TheseareprobablythetwomostpowerfulwordsintheEnglishlanguage.Evenmorepowerfulthanyesandno,s
Tosome,JohnLennon’spianoissacred.Mostmarriedpeopleconsidertheirweddingringssacred.Kidswithnonotionofsanctity
Thebestsolutionistostoppretendingthatpeople’spersonalinformation,suchasSocialSecurityaccountnumbersandbirthda
Thebestsolutionistostoppretendingthatpeople’spersonalinformation,suchasSocialSecurityaccountnumbersandbirthda
Anumberofprocessesorphaseshavebeenidentifiedastypicalofcreativethinking.【F1】Inwhatlogicallywouldbethefirstph
TheU.S.spaceagency,NASA,isplanningtolaunchasatellitethatscientistshopewillanswerfundamentalquestionsaboutthe
Sevenyearsago,agroupoffemalescientistsattheMassachusettsInstituteofTechnologyproducedapieceofresearchwhichsh
It’seasytoscarepeopleaboutwhat’sintheirfood,butthedangerisalmostneverreal.Andthe【C1】______itselfkills.Ta
随机试题
德育过程是由相互制约的四个因素构成的。这四个因素分别是:教育者、_______、_______和德育方法等。
下列关于胃液分泌抑制性调节的叙述中,哪一项是错误的
下列有关剖宫产术后患者的护理,不正确的是
A.肾上腺素B.去甲肾上腺素C.吗啡D.氨茶E.异丙肾上腺素临床上常用作强心药的是
某总承包单位将一医院的通风空调工程分包给某安装单位,工程内容有风系统、水系统和冷热(媒)设备。设备有7台风冷式热泵机组,9台水泵,123台吸顶式新风空调机组,1237台风机盘管、42台排风机,均由业主采购。通风空调工程的电气系统由总承包单位施工。通风空调设
货币的时间价值是由时间创造的,因此,所有的货币都有时间价值。()
某市本年度物业服务合同到期管理服务的物业面积为100万m2,新签订合同接管面积为150万m2,上年物业服务合同期跨入本期继续管理服务的物业面积为50万m2,本年接管后又退出的物业管理服务的物业面积为70万m2,则对该市本年度物业管理服务面积进行统计为(
虚拟局域网可以将网络结点按工作性质与需要划分为若干个______。
intheendmother’ssister
Sallywasabitshy,buttheteacherfoundherquite______discussingarecentfilmwithothers.
最新回复
(
0
)