资源描述:
《湖北黄冈市高考英语阅读理解二轮精练3及解析答案》由会员上传分享,免费在线阅读,更多相关内容在工程资料-天天文库。
1、湖北黄冈市2016高考英语阅读理解精练(3)及(解析)答案阅读下列四篇短文,从每小题后所给的A,B,C或D四个选项中,选出最佳选项。Belowisaselectionfromapopularsciencebook.Ifbloodisred,whyareveins(静脉)blue?Actually,veinsarenotblueatall.Theyaremoreofaclear,yellowishcolou匚Althoughbloodlooksredwhenit'soutsidethebody,whenit'ssittinginavei
2、nnearthesurfaceoftheskimifsmoreofadarkreddishpurplecolour.Attherightdepth,theseblood-filledveinsreflectlessredlightthanthesurroundingskimmakingthemlookbluebycomparison.Whichworksharder,yourheartoryourbrain?Thatkindofdependsonwhetheryou^ebusythinkingorbusyexercising.Your
3、heartworksuptothreetimesharderduringexercise,andshiftsenoughbloodoveralifetimetofillasupertanker.But,inthelongrun,yourbrainprobablytipsit,becauseevenwhenyou'resittingstillyourbrainisusingtwiceasmuchenergyasyourheart,andittakesfourtofivetimesasmuchbloodtofeedit.Whydoteet
4、hfallout,andwhydonrttheygrowbackingrown-ups?Baby(or“milkJteethdonotlastlong;theyfallouttomakeroomforbigger,strongeradultteethlateron.Adultteethfalloutwhentheybecomedamaged,decayedandinfectedbybacteria.Oncethissecondsetofteethhasgrownin,youtedone.WhentheyYegone,theyTegon
5、e.Thisisbecausenaturefiguresyouresetforlife,andwhatcontrolsregrowthofyourteethswitchesoff.Dooldpeopleshrinkastheyage?Yesandno.Manypeopledogetshorterastheyage.But,whentheydo,itisn'tbecausethey'reshrinkingallover.Theysimplyloseheightastheirspine(脊柱)becomesshorterandmorecu
6、rvedduetodisuseandtheeffectsofgravity(重力).Many(butnotall)menandwomendoloseheightastheygetolder.Menloseanaverageof3-4cminheightastheyage,whilewomenmaylose5cmormore.Ifyoulivetobe200yearsold,wouldyoukeepshrinkingtillyouwere,like60cmtalblikealittleboyagain?No,becauseoldpeop
7、ledon'treallyshrink!Itisnotthattheyaregrowingbackwards—theirlegs,armsandbackbonesgettingshorter.Whentheydogetshorter,ifsbecausethespinehasshortenedalittle.Or,moreoften,becomemorebentandcurved.Whydoesspinningmakeyoudizzy(眩晕的)?BecauseyourbraingetsconfusedbetweenwhatyouTes
8、eeingandwhatyou'refeeling.Thebrainsensesthatyourespinningusingspecialgravity-and-motion-sensingorgansinyourinn