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
Nature has devised many ways to protect creatures’ eyes. The most common protection is the eyelid--a fold of skin that closes ov
Nature has devised many ways to protect creatures’ eyes. The most common protection is the eyelid--a fold of skin that closes ov
admin
2011-06-28
46
问题
Nature has devised many ways to protect creatures’ eyes. The most common protection is the eyelid--a fold of skin that closes over the eye, protecting it from damage. Eyelashes are useful for keeping out dust and other irritants, and tears wash away any particles that get through the other defenses.
Some creatures, including most birds, have three eyelids. The upper and lower lids act like human lids and keep out twigs, dirt and sand. The third eyelid, however, is a semitransparent tissue that crosses over the eye from the inside corner to the outside corner. Because of this protective membrane, birds seldom have to blink. They close their eyes only when they go to sleep. In ducks, this third eyelid self as an underwater diving mask that helps the ducks find food.
Most fish and snakes have no eyelids at all. Instead, a hard glassy covering protects their eyes. In fish, water constantly sweeps away dirt from the covering. And a snake’s eyesight is usually so bad that a little dirt obscuring its vision does not disturb it greatly.
Eyelashes defend the eye by shading it from glare. They also act like miniature brushes to remove dust. Camels have lashes that are four inches long to protect their eyes from windblown sand in the desert.
A camel has long eyelashes ______.
选项
A、to keep windblown sand out of its eyes
B、that get in the way of its sight
C、to help it see better
D、to attract other camels
答案
A
解析
最后一段最后一句。骆驼的眼睫毛如此长是为了挡住沙漠中大风吹起的沙子。选项A是正确的。
转载请注明原文地址:https://kaotiyun.com/show/EClC777K
本试题收录于:
英语题库成考专升本分类
0
英语
成考专升本
相关试题推荐
Theforeignstudentadviser(FSA)andmembersofhisorherstaffprovideanumberofservicesimportanttoallforeignstudents
Whatkindsofthingshaveactivistsdonetoprotectresearchanimals?Thepolicethinkthatuseofviolencebyanimalrightsgr
Aspointedoutatthebeginningofthepassage,peopleusedtothinkthatairpollution______.Thispassageisprimarilyabout
Peeringintothe21stcentury,authoritiesonthefutureseeextraordinarychanges.Newscientificbreakthroughwillallowmachi
Anothergoodtitleforthepassagewouldbe______.Thewordskepticalisclosestinmeaningto______.
Thepassageimpliesthatthetelegraphcablewasbuiltmainly______."Defied"inthefifthparagraphprobablymeans"______".
Whywasreadingaloudcommonbeforethenineteenthcentury?Thedevelopmentofsilentreadingduringthenineteenthcenturyind
RomeoandJulietwasprobablywrittenin1595,whenShakespearewasayoung,successfulplaywright.Hehadalreadywrittencomed
ItwasnotuntilthenthatIcametoknowknowledge______onlyfrompractice.
随机试题
A、Itsprotectionisoftenneglectedbychildren.B、Itcannotbefullyrestoredoncedamaged.C、Therearemanyfalsenotionsabou
Sheneedssomecomfort,butIreallycan’tthinkofanything______(suit)tosay.
治疗干霍乱的主方是治疗湿热泄泻的主方是
患者,女,24岁。产后4周恶露不止,量多,色淡红,质稀,小腹空坠,神疲体倦,舌淡苔薄白,脉缓弱。其证候是
扣缴义务人未按规定设置、保管代扣代缴、代收代缴税款账簿或者保管代扣代缴、代收代缴税款记账凭证及有关资料的,由税务机关责令改正,逾期不改正的,处以___________以下的罚款;情节严重的,处以___________的罚款。()
下列各句句意明确、不存在歧义的是()。
玉米的正常市场价格为每公斤1.86元到2.18元,近期某地玉米价格涨至每公斤2.68元。经测算,向市场每投放储备玉米100电,每公斤玉米价格可下降0.05元。为稳定玉米价格,向该地投放储备玉米的数量不能超过()。
【《圣武记》】北京师范大学2000年中国史学史真题
Childrentodayspendmoretimestareatcomputer【S1】______andTVscreensbothatschoolandathome.Scientific【S2】______
A、Anexportsalesmanworkingoverseas.B、Atraineeworkingthrougheverybranch.C、Aproductionmanagerinabranch.D、Apolicy
最新回复
(
0
)