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
An eagle wheels overhead against a crystalline blue sky, Martin Flanagan walks toward a grove of towering cottonwood trees besid
An eagle wheels overhead against a crystalline blue sky, Martin Flanagan walks toward a grove of towering cottonwood trees besid
admin
2015-01-30
53
问题
An eagle wheels overhead against a crystalline blue sky, Martin Flanagan walks toward a grove of towering cottonwood trees beside the Yellowstone River, which is the color of chocolate milk due to the spring rain.
As Mr. Flanagan leaves the glaring sun of the prairie and enters the shady grove, his eyes search for a specific tree. As he reaches a narrow-leaf cottonwood, a towering giant, he cranes his neck to look at the top. "This is the one I plan to nominate for state champion," he says, petting the bark with his hand. "It’s beautiful isn’t it?"
When Europeans first came to North America, one of the largest primeval forests in the world covered much of the continent. Experts say a squirrel could have traveled from the Atlantic coast to the Mississippi River without touching the ground. But only about 3 percent of America’s native old-growth forest remains, and many of the trees they hold are those that were not big enough to attract a logger’s eyes. The result is a generation of trees that barely resemble the native forests that once covered the country.
That makes some scientists suspect that the surviving forests have lost much of their genetic quality, the molecular muscle that made them dominate the landscape. When the loggers swept through, these scientists say, only poor specimens were left to reproduce. Other researchers wonder whether environmental factors or just plain luck may explain a good part of the supertrees’ success.
To answer those questions, the mightiest trees of their types, or genetically identical offspring, must be preserved for study, and that is what is being done by a handful of enthusiasts, including Mr. Flanagan and David Milarch, a nurseryman from Copemish, Mich. They are searching out the largest tree of each species and taking cuttings of new growth to make copies of genetic clones of the giants. With tissue culture and grafting, they have reproduced 52 of the 827 living giants and are planning the offspring in what they call "living libraries." More than 20,000 offspring have been planted.
Directions: Complete the following sentences with information given in the passage in a maximum of 10 words for each blank.
Water in the Yellowstone River turned______because of the spring rain.
选项
答案
dark brown
解析
转载请注明原文地址:https://kaotiyun.com/show/QKVK777K
本试题收录于:
C类竞赛(非英语专业本科)题库大学生英语竞赛(NECCS)分类
0
C类竞赛(非英语专业本科)
大学生英语竞赛(NECCS)
相关试题推荐
(1)Youwon’talwaysgetalongwitheveryoneyouworkwith.Butwhenthere’sfrictionbetweenyouandyourboss,that’saproble
SuggestionsforEffectiveResearch-basedAssignmentsIntroduction.well-designedassignments—teachstudentsvaluab
DoSomethingtoImproveYourLifeⅠ.Wrongopinionstowardslife1)thewrongopinionsofpeople—havetoacceptwha
(1)BecauseImarriedaphotographer,oncewehadchildren,ourholidaycardsofcoursebecamevehiclesfortheircutenessandh
Itwasonlyafewweeksaftermysurgery,andIwenttoDr.Belt’sofficeforacheckup.Itwasjustaftermyfirstchemotherapy
LOOKONTHEBRIGHTSIDEDoyoueverwishyouweremoreoptimistic,someonewhoalways【16】ex______tobesuccessful?Havings
Thelessthesurfaceofthegroundyieldstotheweightofafully-loadedtruck______tothetruck.
Coffeeismadefromthebeansthatgrowinthefruitofthecoffeeplant.Thereare【16】usu______twobeansineachpodoffruita
Industrialpsychologyistheapplicationofvariouspsychologicaltechniquestotheselectionandtrainingofindustrialworkers
TheOlympicmottoismadeupofthreewords:FASTER—HIGHER—STRONGER.ThemottocanbecomparedtotheOlympiccreed(宗旨)whichs
随机试题
鲍莫尔的“销售最大化”模型表达了他对经理人员强调销售额的重要性的理解。下列选项中,关于该模型的表述错误的有()。
职业技能鉴定试题应由职业技能鉴定站编制。()
标准铂电阻温度计的电阻与温度的关系表达式用W(t)与t的关系代替Rt与t的关系式,其优点是可提高计算精度。
锁骨中线是指
引起Ⅱ型呼吸衰竭最常见的诱因是()。
关于起诉与受理的表述,下列哪些选项是正确的?(2012—卷三—79,多)
专利权既可以作为经济法律关系的内容,也可以作为经济法律关系的客体。( )
支持子程序调用的数据结构是()。
Itisoftendifficultto______betweenamereexaggerationandadeliberately.(2006年中国矿业大学考博试题)
A、Controlofnaturalhazards.B、Controlofheavytraffic.C、Controlofheartdisease.D、Controlofman-madehazards.D短文说,“在人类历史
最新回复
(
0
)