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
(31) with the human eye, a cat’s (32) have more rods than cones, (33) helps the cat see in the dark. Cats also have elliptical p
(31) with the human eye, a cat’s (32) have more rods than cones, (33) helps the cat see in the dark. Cats also have elliptical p
admin
2009-06-24
49
问题
(31) with the human eye, a cat’s (32) have more rods than cones, (33) helps the cat see in the dark. Cats also have elliptical pupils that open and close faster and can become larger than our round (34). In addition, cats and some (35) nocturnal animals have a mirror like membrane on the back of their eyes, which reflects the light passing through the rods back through them in the, opposite direction, This "double exposure" allows cats to (36) well in near darkness.
The human eye changes gradually (37) age, (38) the changes are critical. In darkness, eyes adapt (39) widening the pupils to let in as much light as possible. (40) you get older, these muscles weaken and do not respond as well (41) the need to let in more light.
The result is a small (42) when you try to see in poor light. It’s (43) if your eyes were still young but you were wearing sunglasses at night. There is also evidence that as we age we lose more rods (44) cones.
In the young eye, rods (45) cones by nine to one in the part of the retina called the macula. But an autopsy study of older adults found that while the cones (46) intact, almost a third of the rods in the macula had been lost.
The less responsive muscles in the iris also affect the eye’s ability to adjust when the intensity of light changes, (47) as when a car with its headlights on approaches and then passes.
In older eyes, this phenomenon, (48) dark adaptation, takes longer, which (49) you see less well in the dark after being in the light, and vice versa. The diminished number of rods may be a factor, but in addition, the light-sensitive pigment in the rods regenerates more slowly in (50) eyes.
选项
答案
as
解析
转载请注明原文地址:https://kaotiyun.com/show/q7Td777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
BritishGovernmentWhenBritishvotersgotothepollsduringGeneralElectionstodecide(51)willgovernthemtheyusuallyhave
ThinkingfromateacherAsthefallsemesterended,mystudentshadachancetoturntotablesontheirteacher.Theygottogra
TeachingPoetryNopoemshouldeverbediscussedor"analyzed",untilithasbeenreadaloudbysomeone,teacherorstudent.
NewIdeasIceland’sPresidentOlafurGrimssonistryingtodrivecarbondioxide(二氧化碳)undergroundto
Thenucleusoftheatomiscomposedofswiftlymovingprotonsandneutronsthatareheldtogetherbyverystrongforces.
TheDifferencebetweenManandComputerWhatmakespeopledifferentfromcomputerprograms?Whatisthemissingelementthat
TheDifferencebetweenManandComputerWhatmakespeopledifferentfromcomputerprograms?Whatisthemissingelementthat
TheDifferencebetweenManandComputerWhatmakespeopledifferentfromcomputerprograms?Whatisthemissingelementthat
(31)withthehumaneye,acat’s(32)havemorerodsthancones,(33)helpsthecatseeinthedark.Catsalsohaveellipticalp
ChrisBoningtonhasclimbedMountEverestatleasttwicesofar.
随机试题
有人说,凡是知识都是科学的,凡是科学都是无颜色的,并且在追求知识时,应当保持没有颜色的态度。假使这种说法不随意扩大,我也认同。但我们要知道,只要是一个活生生的人,便必然有颜色。对无颜色的知识的追求,必定潜伏着一种有颜色的力量,在后面或底层加以推动。这一推动
下列关于刑罚权的说法正确的有:()
下列不属于招投标市场客体即交易客体的是()。
以地表水为水源的给水厂常采用的水处理工艺包括()。
甲上市公司为增值税一般纳税人,适用的增值税税率为17%,所得税税率为25%。假定该公司20×7年所有资产和负债项目的账面价值均等于其计税基础,并假定发生了如下经济业务:(1)购入材料一批,货款1万元,增值税0.17万元,材料验收入库,款项未付。(2)借
个人汽车贷款的还款方式包括()。
下列有关舞弊导致的重大错报风险的说法中,不恰当的是()。
下面属于建构主义教学模式的是()
22,306,512,820,1330,()。
VideogameshavebecomeincreasinglypopularinbotharcadesandtheaverageAmericanhome.Peopleofallagesandfromallwalk
最新回复
(
0
)