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 adult giraffe’s head is about six feet above its heart. This means that to 【C1】______ enough blood up to the brain the circul
An adult giraffe’s head is about six feet above its heart. This means that to 【C1】______ enough blood up to the brain the circul
admin
2012-12-13
44
问题
An adult giraffe’s head is about six feet above its heart. This means that to 【C1】______ enough blood up to the brain the circulatory 【C2】______ must be strong enough to keep the blood at very high pressure.
Biologists have known for some time that giraffes solve this problem by having 【C3】______ high blood pressure, about 【C4】______ that of human beings. But an international team of biologists began to 【C5】______ about this. If giraffes have such high blood pressure, they should have a 【C6】______ problem with swelling in their legs and feet. Why don’t giraffes have swollen feet?
Giraffes should have 【C7】______ problem, too. Every time they bend heads 【C8】______ to drink, the blood should 【C9】______ to their heads and have a hard time 【C10】______ back up (when the head is down) to the heart. How come giraffes don’t black out when they drink?
The answer to the 【C11】______ feet problem, the researchers found, is that giraffes have 【C12】______ the researchers call a "natural anti-gravity suit". It 【C13】______ out that the skin and other 【C14】______ in their legs and feet are 【C15】______ stiffer and tougher than those of other 【C16】______ . As a result, the blood vessels in the leg cannot swell.
Therefore, the blood has nowhere to go but back to the heart. What about blood rushing to the head 【C17】______ the giraffe bends down to drink? The researchers found that the giraffe’s jugular vein, which 【C18】______ blood from the head back to the heart, has lots of one-way valves in it. In the giraffe’s neck, there are lots of muscles that flex and relax repeatedly as the animal moves its head and sucks 【C19】______ drinking water. By squeezing the valved jugular vein, they 【C20】______ blood moving back to the heart even while the animal is drinking.
【C3】
选项
A、unusually
B、generally
C、uncomfortably
D、commonly
答案
A
解析
词义辨析题,空格所在句意为:生物学家已经发现长颈鹿有______很高的血压能解决这个问题,由此可知,这个很高的血压应该是与众不同的,所以A正确
转载请注明原文地址:https://kaotiyun.com/show/gCw7777K
0
大学英语四级
相关试题推荐
A、Julie’sdressisnotoutdated.B、Julielooksfineinthatdress.C、Julie’sdressdoesnotsuither.D、Julieshouldfollowthe
A、Heisveryoldnow.B、Heisingoodhealth.C、Helivesinthecitynow.D、Heprefersdrivingacar.C短文最后提到Icertainlyhopeto
Participationinhighschoolsportsisnotaconstitutionalright.【C1】______.itisaprivilege,paidforbytaxpayers,opento
Withtheworld’spopulationestimatedtogrowfromsixtoninebillionby2050,researchers,businessesandgovernmentsarealre
Throughouthistorythebasicunitofalmosteveryhumansocietyhasbeenthefamily.Membersofafamilylivetogetherunderthe
A、Toexchangeideas.B、Toprovetheirvalue.C、Toachievesuccessinlife.D、Toovercometheirfearofsilence.D选项均以不定式开头表明,本题考
A、15%.B、25%.C、27%.D、73%.D选项表明本题考查数字。短文中提到有多少美国公司认为办公室养宠物是有益的,其中提到,AstudyofmajorU.Scompaniesshowedthat73%foundoffice
Thiswashingmachineis______totheotherwashingmachinesonthemarket.
A、Beforefinishingschool.B、Afterfinishinguniversity.C、Duringheruniversitycourse.D、Betweenschoolanduniversity.D选项均以时
A、Someoneoutoftouch.B、Missingitems.C、Jobvacancies.D、Someonetodate.A本题询问人们经常Google什么。短文中间提到人们经常寻找失去联系的人,但是寻找朋友、亲戚、同事和邻
随机试题
关于成倍节拍流水施工特点的说法,错误的有()。
《公民道德建设实施纲要》中提出的“爱国守法、明礼诚信、团结友善、勤俭自强、敬业奉献”,是我国公民应当遵守的()
下列哪种消毒措施对HIv不敏感()
某医院采用国际招标采购两台超声波诊断仪,招标文件正式报送商务部机电和科技产业司备案前,为了缩短采购时间,招标人先行在其所在省日报上发布了一个招标公告,招标公告中载明的投标截止时间和开标时间为“另行通知”,并开始发售招标文件。收到招标文件备案复函后,招标人又
()的理论基础是新古典经济学有关资源优化配置的理论。
下列关于投标保证金的表述中,正确的是()。
高科技运动鞋是利用高科技结合人体运动力学原理研究出来的新一代运动鞋。它们采用各种特殊的材料,重量轻,避震效果好。同时,它们附着力强,便于运动员控制身体,保持正确姿势,避免滑倒。此外,它们还有回输功能,利用鞋眼中央位置的气垫吸震并同时吸收能量产生反弹力,使运
圆面积为().
对于长度为n的顺序存储的线性表,当随机插入和删除一个元素时,需平均移动元素的个数为【】。
WelcometovisitourcompanyandIamverygladtohavetheopportunitytointroduceourcompanytoyouall.Ourcompanywasest
最新回复
(
0
)