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#英语思维#
#英语#
#眼睛#
Why are human eye colours restricted to brown, blue, green, and in extremely rare cases, red, as opposed to other colours?【译】为什么人眼的颜色仅限于棕色、蓝色、绿色，在极少数情况下，还有红色，而不是其他颜色？【单词】eye [ahy][aɪ] n. 眼睛【单词】colours 原型 colour（也可以写作color） ['kʌlə] n. 颜色【单词】restricted 原型：restrict [ri-'strikt][rɪ'strɪkt] vt. 限制；约束【单词】brown [broun][braʊn] adj. 棕色的；褐色的【单词】blue [bloo][bluː] adj. 蓝色的【单词】extremely [ik-'streem-lee][ɪk'striːmli] adv. 非常；极其【单词】rare [rair][reə] adj. 罕见的；珍贵的【单词】opposed 这里是过去分词作形容词用，表示“相反的”， 原型：oppose [uh-'pohz][ə'pəʊz] v. 反对；对抗；使对立
Eye color is in the Iris, and the Iris has two layers, a back layer that's always fully pigmented, and a thicker front layer.【译】眼睛的颜色在虹膜上，虹膜有两层，一层是完全着色的后一层，另一层是较厚的前一层。【单词】layer ['ley-er]['leɪə] n. 层【单词】fully ['foo l-ee, 'foo l-lee]['fʊli] adv. 十分地；完全地；全部【单词】pigmented [pɪɡ'mentɪd] adj. 有颜色的【单词】thicker 原型：thick 形容词比较级 [thik][θɪk] adj. 厚的；浓密的；粗的【单词】Iris ['ahy-ris]['aɪrɪs] n. 虹膜
【解析】虹膜是血管膜的最前部，呈环状。位于眼睛的晶状体的前方，将眼房分为前房和后房。
The pigment is melanin, same that makes our skin different colors.【译】色素是黑色素，同样使我们的皮肤呈不同的颜色。【单词】pigment ['pig-muhnt]['pɪɡmənt] n. 色素； 颜料【单词】melanin ['mel-uh-nin]['melənɪn] n. 黑色素【单词】skin [skin][skɪn] n. 皮肤；外皮
Now when the front layer is densely pigmented, it appears dark, like brown or even black (though shine a bright enough light and you'll see black eyes are just very dark brown).【译】现在，当前一层是浓密的色素，它看起来很暗，像棕色，甚至黑色（尽管在足够亮的光线照射下，你会看到黑色的眼睛其实只是非常深的棕色）。【单词】densely [dens][densli] adv. 密集地；浓厚地【单词】shine [shahyn][ʃaɪn] v. 照耀；发光；投光于【单词】bright [brahyt][braɪt] adj. 明亮的；阳光的；生动的
If it's not pigmented, it appears light blue.【译】如果没有着色，它就会呈现淡蓝色。
Why?【译】为什么？
Same reason the sky's blue, light scatters in it.【译】同样的原因，天空是蓝色的，光在其中散射。【单词】sky [skahy][skaɪ] n. 天空【单词】scatters 原型：scatter ['skat-er]['skætə] vt. 散播；撒 vi. 分散；消散
Light scattering is a different topic, but basically short wavelengths (ie blue) bounce differently in the fluffy front layer without pigment.【译】光散射是一个另一个话题，但基本上短波长（即蓝色）在蓬松的前一层没有色素而反射的方式不同。【单词】topic ['top-ik]['tɒpɪk] n. 题目；话题；标题【单词】basically ['bey-sik-lee]['beɪsɪkli] adv. 基本上；主要地【单词】wavelengths 原型：wavelength ['weyv-length]['weɪvleŋθ] n. 波长；波段【单词】bounce [bouns][baʊns] vi. 弹起【单词】differently ['dif-er-uhnt-lee, 'dif-ruhnt‐]['dɪfrəntli] adv. 不同地【单词】fluffy ['fluhf-ee]['flʌfi] adj. 毛绒绒的；蓬松的；空洞的
What about in between?【译】中间呢？
Well it turns out if there's pigment but it's not super dense, it's a bit of a lighter brown or dark orange.【译】如果有色素，但不是超浓的，会是浅棕色或深橙色。【单词】super ['soo-per]['suːpə] adj. 超级的；极好的【单词】dense [dens][dens] adj. 密集的；稠密的；浓密的【单词】lighter ['lahy-ter]['laɪtə] adj. light的形容词/副词比较级，更浅的【单词】orange ['awr-inj, 'or-]['ɒrɪndʒ] adj. 橙色的
We call these amber eyes.【译】我们称之为琥珀色的眼睛。【单词】amber ['am-ber]['æmbə] adj. 琥珀的；琥珀色的
If it's between amber and blue, then it's like a cross between light orange and blue.【译】如果它介于琥珀色和蓝色之间，那么它就像是浅橙色和蓝色之间的混合。【单词】cross [kraws, kros][krɒs] n. 交叉
That's how you get green eyes.【译】人就是这样有了绿色的眼睛的。
So that's how you get the spectrum: from blue to green to amber to brown to black.【译】这就是光谱推进的方式：从蓝色到绿色到琥珀色到棕色到黑色。【单词】spectrum ['spek-truhm]['spektrəm] n. 系列；幅度；范围；光谱
So what about "red" or "violet" eyes?【译】那“红”色或“紫”色的眼睛呢？【单词】violet ['vahy-uh-lit]['vaɪələt] adj. 紫色的
Turns out I lied in the beginning; that back layer I mentioned that's always pigmented isn't in a medical condition: Albinism.【译】哈哈，其实我一开始就说的不对；我提到的一直有色素沉着的那一层不是医学上的：白化病。【单词】lied 原型：lie [lahy][laɪ] v. 说谎【单词】beginning 原型：begin [bih-'gin][bɪ'ɡɪn] v. 开始【单词】mentioned 原型：mention ['men-shuhn]['menʃn] vt. 提到；说起【单词】medical ['med-i-kuhl]['medɪkl] adj. 医疗的；医学的；医药的【单词】condition [kuh n-'dish-uh n][kən'dɪʃn] n. 条件；情况【专有名词】Albinism ['al-buh-niz-uhm]['ælbɪnɪzəm] n. 白化病；皮肤变白症
These folks unfortunately have a defect in producing melanin pigment, which is why they all have fair skin and light hair and such.【译】不幸的是，这些人在产生黑色素方面有缺陷，这就是为什么他们都有浅白色的皮肤和浅色的头发等等。【单词】folks 原型：folk [fohk][fəʊk] n. 人们；（某类或来自某个地方的）人【单词】unfortunately [uhn-'fawr-chuh-nit][ʌn'fɔːtʃənətli] adv. 不幸地；遗憾地【单词】defect ['dee-fekt]['diːfekt] n. 缺点；缺陷【单词】fair [fair][feə] adj. （皮肤、毛发等）浅色的；白皙的
So why red?【译】为什么会是红色呢？
It's the same reason you can get red eyes in flash photography; the red is the color of the retina in the back of the eye.【译】同样的道理，你可以在闪光摄影中看到红色的眼睛；红色是眼睛后面视网膜的颜色。【单词】flash [flash][flæʃ] n. 闪光（灯）【单词】photography [fuh-'tog-ruh-fee][fə'tɒɡrəfi] n. 摄影【单词】retina ['ret-n-uh, 'ret-nuh]['retɪnə] n. 视网膜
Flash photography causes you to accidentally image peoples retinas.【译】拍照时使用闪光灯会让你不小心拍到别人的视网膜。【单词】accidentally [ak-si-'den-tl][ˌæksɪ'dentəli] adv. 偶然地；意外地；附带地【单词】image ['im-ij]['ɪmɪdʒ] vt. 拍摄；描绘
Now without the pigment in the back layer of the iris, the iris almost functionally becomes like Saran Wrap; it's clear and doesn't block out light anymore.【译】现在没有色素在虹膜的底层，虹膜的功能几乎变得像合成纤维包装；它是清晰的，不再遮光。【单词】functionally ['fuhngk-shuh-nl]['fʌŋkʃənəli] adv. 功能上；机能上【单词】block out v. 阻塞，阻断【单词】anymore [en-ee-'mawr, -'mohr]['enɪmɔː] adv. (通常用于疑问句或否定句中，与not连用)再，也，还【专有名词】Saran [suh-'ran][sə'ræn] n. [化]丝龙(一种合成纤维)【单词】wrap [rap][ræp] n. 包装材料
So when you see red (or violet) eyes, you're seeing retina through their Iris.【译】所以当你看到红色（或紫色）的眼睛时，你是通过虹膜看到视网膜的。
Side note: this is one reason why folks with albinism have poor vision.【译】旁注：这是白化病患者视力差的原因之一。【单词】vision ['vizh-uhn]['vɪʒn] n. 视力；视觉
The purpose of the iris is to act like a camera aperature.【译】虹膜的作用就像照相机的光圈。【单词】purpose ['pur-puhs]['pɜːpəs] n. 目的；决心；意图【单词】camera ['kam-er-uh, 'kam-ruh]['kæmərə] n. 照相机；摄像机
Without pigment, it can't block out light like an aperature, removing a whole element of the focusing system of the eye.【译】如果没有色素，它就无法像光圈一样阻挡光线，从而使眼睛的聚焦系统的完全失效。【单词】removing 原型：remove [ri-'moov][rɪ'muːv] v. 消除【单词】element ['el-uh-muhnt]['elɪmənt] n. 要素；元素【单词】focusing 原型：focus ['foh-kuhs]['fəʊkəs] v. （使）集中；聚集；聚焦
Disclaimer: this is a bit of an oversimplification of how eye colors work, but it's fundamentally not too far off.【译】免责声明：这是一个可能有些过于简单化的眼睛颜色的原理描述，但它基本与事实差距不大。【单词】disclaimer [dis-'kley-mer][dɪs'kleɪmə] n. 放弃；弃权；免责声明【单词】oversimplification [oh-ver-'sim-pluh-fahy][ˌəʊvəˌsɪmplɪfɪ'keɪʃn] n. 过于简化【单词】fundamentally [fuhn-duh-'men-tl-ee][ˌfʌndə'mentəli] adv. 从根本上；基本地
The genetics that go into eye color get very complex, don't think it's some single gene thing; I know this explanation makes it seem like there's just one toggle, but that's not how the genetic part of it works.【译】关于眼睛颜色的基因很复杂，不要认为这是某个单一的基因引起的；我知道刚才这个解释使它看起来好像只有一个决定因素，但这不是基因部分如何起作用的全部。【短语】part of ... （某事物的）一部分；例句：He received part of his education in England. 他有一部分教育是在英国接受的。【单词】genetics 原型：genetic [juh-'net-ik][dʒə'netɪk] adj. 遗传的；基因的；起源的【单词】complex [kuhm-'pleks]['kɒmpleks] adj. 复杂的【单词】gene [jeen][dʒiːn] n. 基因【单词】explanation [ek-spluh-'ney-shuhn][ˌeksplə'neɪʃn] n. 解释；说明【单词】toggle ['tog-uhl]['tɒɡl] n. 触发器；开关
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