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
专升本
An adult giraffe’s head is about six feet above its heart. This means that to【C1】______enough blood up to the brain the circulat
An adult giraffe’s head is about six feet above its heart. This means that to【C1】______enough blood up to the brain the circulat
admin
2016-03-05
53
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(晕倒)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(颈静脉的)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(曲折;收缩)and relax repeatedly as the animal moves its head and【C19】______up drinking water. By squeezing the valved jugular vein, they【C20】______blood moving back to the heart even while the animal is drinking.
【C9】
选项
A、crush
B、brush
C、push
D、rush
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/OTHC777K
本试题收录于:
英语题库普高专升本分类
0
英语
普高专升本
相关试题推荐
By【B1】______afewsimpletechniques,parentswhoreadtotheirchildrencangreatlyincreasetheirchildren’slanguagedevelopm
TheUnitedStatesiswell-knownforitsnetworkofmajorhigh-waysdesignedtohelpadrivergetfromoneplacetoanotherinth
TheUnitedStatesiswell-knownforitsnetworkofmajorhigh-waysdesignedtohelpadrivergetfromoneplacetoanotherinth
Seventypercentapproved______thewayshehandledthesituationwhilethirtypecentdisapproved.
A、Shewonthefirstprizeinthecyclerace.B、Sheboughtthebeautifulracingcyclebycollectingmoney.C、Shewastaughttocy
InAmerica,itisnotcustomaryforparentstolivewiththeirmarriedchildren.
A、Itwasbetter.B、Itwasadisaster.C、Itwasnotgoodenough.D、Itwasgreat.D
______tothequestionofrefreshments,Ishouldthinklemonadeandsandwicheswillbeenough.
WhenIwaslearningcalligraphy(书法),myteachertoldmeastory.Acalligraphertaughthandwriting.Oneofhisstudentswho
随机试题
心力贮备(cardiacreserve)
[2007年第76题]对于放散热或有害物质的生产设备布置,以下哪种说法是错误的?
下列关于房产税的说法,正确的是()。
如果处在谷底的经济增长率仍为正值,即经济总量只是相对减少而非绝对减少,则为古典型周期。()
销售活动的作用是通过产品的销售,满足消费者的需求,实现产品的价值和使用价值。
我国社会主义职业道德建设的基本原则是()
在原型内化阶段,对学生言语培养的重点应放在()。
应怎样正确对待非正式群体?
Howmayplanetsarethereinthesolarsystemrevolvingaroundthesun?
【S1】【S2】
最新回复
(
0
)