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
Wonder Webs Spider webs are more than homes, and they are ingenious traps. And the world’s best web spinner may be the Golde
Wonder Webs Spider webs are more than homes, and they are ingenious traps. And the world’s best web spinner may be the Golde
admin
2011-01-02
60
问题
Wonder Webs
Spider webs are more than homes, and they are ingenious traps. And the world’s best web spinner may be the Goldern Orb Weaver spider. The female Orb Weaver spins a web of fibers thin enough to be invisible to insect, yet【51】 enough to snare a flying bird without breaking.
The secret of the web’s strength. A type of super-resilient【52】 called dragline. When the female spider is ready to【53】 the web’s spokes and frame, she uses her legs to draw the airy thread out through a hollow nozzle in her belly. Dragline is not sticky, so the spider can race back and forth along【54】 to spin the web’s trademark spiral.
Unlike some spiders that weave a new web every day, a Golden Orb Weaver【55】 her handiwork until it fails apart, sometimes not for two years. The silky thread is five times stronger than steel by weight and absorbs the force of an impact three times better than Kevlar, a high strength human-made【56】 used in bullet-proof vests. And thanks to its high tensile strength, or the ability to resist breaking under the pulling force called tension, a single strand can stretch up to 40 percent longer than its original【57】 and snap back as well as new. No human-made fiber even comes【58】.
It is no【59】 manufacturers are clamoring for spider silk. In the consumer pipeline: high-performance fabrics for athletes and stockings that never run. Think parachute cords and suspension bridge cables. A steady【60】 of spider silk would be worth billions of dollars— but how to produce it? Harvesting silk on spider farms does not【61】because the territorial arthropods have a tendency to devour their neighbors.
Now, scientists at the biotechnology company Nexia are spinning artificial silk modeled after Goldern Orb dragline. The【62】step: extract silk-making genes from the spiders. Next, implant the genes into goat egg cells. The nanny goats that grow from the eggs secrete dragline silk proteins in their【63】. "The young goats pass on the silk-making gene without【64】help from us," says Nexia president Jeffrey Turner. Nexia is still perfecting the spinning process, but they hope artificial spider silk will soon be snagging customers【65】the real thing snags bugs.
选项
A、breadth
B、length
C、height
D、strength
答案
B
解析
拉伸之后对比的是原长度,可知B.length符合题意。A.breadth宽度:B.length长度;C.height高度;D.strength力度。
转载请注明原文地址:https://kaotiyun.com/show/zVLd777K
本试题收录于:
职称英语理工类A级题库职称英语分类
0
职称英语理工类A级
职称英语
相关试题推荐
Readingthejobad,hewonderedwhetherhewaseligibletoapplyforit.
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
AWonderfulChipItistiny,onlyaboutaquarterofaninchsquare,andquiteflat.Underamicroscope,itresemblesasty
随机试题
基金管理人应当自收到核准文件之日起几个月内进行基金募集?()
形成肾内髓部组织间液高渗的物质是
排便时及排便后有马鞍型疼痛特点的是
A.合欢皮B.珍珠C.酸枣仁D.远志E.茯苓善于解郁安神、活血消肿的药物是()。
房地产开发公司对商品住宅的保修期从商品住宅()之日起计算。
若承包商未能在要求的21天内进行竣工试验,而雇主人员着手自行实施试验,那么( )。
饭店治安管理的基本环节包括()。
××市人民政府关于“有关问题”的批复市交通委、市发展改革委、市财政局:你们联合上报的《关于××高速公路收取车辆通行费有关问题的请示》收悉。经认真研究作出如下批复:根据《中华人民共和国公路法》、国务院《收费公路管理条例》及有关文件规定,基本同意××
设随机变量X服从参数为2的指数分布,则随机变量Y=min{X,2)的分布函数().
Whatisanappropriatetitleforthispassage?Whatisawayfortheprospectiveemployeetoshowhis/heragreementwiththebo
最新回复
(
0
)