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
A、They’re much larger than spiders. B、They’re quite delicate. C、They have unusual ways of gathering food. D、They developed a lon
A、They’re much larger than spiders. B、They’re quite delicate. C、They have unusual ways of gathering food. D、They developed a lon
admin
2004-12-28
49
问题
On Monday we talked about insects, and how they gather food. Today I’d like to talk about the common garden spider and how it captures its prey with net-like structure it first produced almost 200 million years ago. I mean, of course a spider web. What’s interesting is why such a delicate structure isn’t hard. When a fast-flying insect crashes into it, and compared with the spider, these insects can be huge and really heavy. In fact capturing a large insect in a spider web could be compared to capture an airplane in a fishing net. So, how can the web offset such a shock without breaking? is it just because the thread is made of so strong? well, experts analyze spider webs using a computer program designed when an insect crashed and caught and they found the structure of the web, the way of threads connected together helps balance the strength and tensions caused by the impact and spread them all across the web this saves the web from being destroyed and by the way, suggests some creative new ideas that human might use in designing buildings. The biggest surprise, though, is the role of air resistance in cushioning the shock of collision. The computer model showed that dragging a tightening thread from a spider web through the air is a lot like pulling a heavy rope through water. And since air resistance acts on many threads all across the web its amazing effect that multiplies many times. And this definitely helps the web survive the impact
选项
A、They’re much larger than spiders.
B、They’re quite delicate.
C、They have unusual ways of gathering food.
D、They developed a long time before spiders.
答案
A
解析
Q:?what?does?the?speaker?say?about?some?of?the?insects?that?spiders?capture??
转载请注明原文地址:https://kaotiyun.com/show/Mp8O777K
0
托福(TOEFL)
相关试题推荐
TacklingHungerinMsekeniATherearenotenoughclassroomsattheMsekeniprimaryschool,sohalfthelessonstakeplaceinth
Accordingtothewriter,whatproblemsarefacedwhenregulatingvideogames?
Accordingtothewriter,whatviewaboutvideogamesdoesSusanGreenfieldputforwardinhernewbook?
AtthestartofhertalkRebeccapointsoutthatnewgraduatescanfindithardto______.Whenshehaddevelopedaportfolioo
Choosethecorrectletter,A,BorC.ResearchprojectonattitudestowardsstudyTonyisparticularlyimpressedbyPhoebe’sab
Completethesentencesbelow.WriteNOMORETHANTHREEWORDSforeachanswer.Computersinsome______cannotbelinkedtothene
Completethenotesbelow.WriteNOMORETHANTWOWORDSforeachanswer.TheArgussystemDevelopedbyRo
A、Whatspiderseat.B、Whyspiderwebsaresostrong.C、Howcomputerscanbeusefultobiologists.D、Hownewkindsofstructuresm
IsEarthGettingWarmer?TheNationalAcademyofSciencesclaimedrecentlythatpeopleshouldcautionratherthanpanicabou
随机试题
背景材料:有一位顾客要求美国一家保险公司偿付一笔赔偿费。保险公司先是答应给他一笔慷慨的赔偿费,同时,该公司具体负责清算赔偿的人士也告诉他说,自己下星期就要去度假,要求这位顾客在星期五之前把所有资料送来核查,否则赔偿将无法实施。于是这位顾客加班加点,终于在星
下列哪项是心肌梗死的“损伤型”心电图改变
在单代号搭接网络计划中,STFi—j表示()。
海关的性质和任务各是什么?
某小学取消了各种形式的统,废除了“百分制”,而代之以“评语+特长+等级”的评价标准。学校的做法()。
《教师职业道德行为规范》提出,教师在处理与家长的关系时,要与家长沟通。关于教师与家长的沟通,下列说法正确的是()。
A、B、C、D、E是5个不同的整数,两两相加的和共有8个不同的数值,分别是17、25、28、31、34、39、42、45,则这5个数中能被6整除的有几个?
提出自主、自产、抵制英国和民族教育四大纲领的印度国大党领导人是()。
恩格斯指出,“德国的理论上的社会主义永远不会忘记,它是站在圣西门、傅立叶和欧文这三个人的肩上的。”这段话说明科学社会主义直接的思想来源是
When______theroomduringafiredrill,pleaseproceedcalmlybutquickly.
最新回复
(
0
)