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
Why roses are red and violets are blue? Did you ever wonder why you see the colors you do or if other animals see the same co
Why roses are red and violets are blue? Did you ever wonder why you see the colors you do or if other animals see the same co
admin
2010-06-18
56
问题
Why roses are red and violets are blue?
Did you ever wonder why you see the colors you do or if other animals see the same colors that you see? We see light that bounces off of things around us. When the light enters our eyes, special cells tell our brains about the light. These cells are called photoreceptors. Light is made of little bits called photons. When the sun shines, trillions and trillions of these little bits of light fall on the earth. The photons bounce off of almost everything and some of them enter our eyes. Those bits that enter our eyes allow us to see. So, where does the color come from?
Starting in the 1600s with Sir Isaac Newton, scientists have believed that there are different kinds of photons. Different types give rise to our sense of colors. The different photons are said to have different wavelengths. Sunlight contains all the different wavelengths of photons. The visible wavelength colors can be seen when you look at a rainbow. Raindrops acting as natural prisms produce the colors.
HOW do our photoreceptors work?
We have two main types of photoreceptors called rods and cones. They are called rods and cones because of their shapes. These cells are located in a layer at the back of the eye called the retina. Rods are used to see in very dim light and only show the world to us in black and white. This is why you see only black and white when you are outside in the evening or in a dimly lit room. The other type of photoreceptors, the cones, allow us to see colors. They are not as sensitive as the rods so they only work in bright light. There are three types of cones, one for each of the three main colors we see, red, green and blue.
Some people have a genetic defect that makes one or more of the cones fail. This condition is known as color deficiency. You may have heard it called color blindness. Color blindness is fairly common, affecting about nine percent of all humans.’ It is much more common in men than in women. To test for color blindness a special picture called an Ishihara test is used.
What about other animals? What kind of colors do they see? Most animals see fewer colors than we do, but some see more! We know this by looking at how many kinds of cone
photoreceptors they have. Another good indication of what an animal can see is by looking at their own colors. The colors of their prey are also an indication of an animals ability to see color.
It can be inferred from the passage that ______.
选项
A、the human eye is sensitive to all wavelengths
B、colors are related to wavelengths
C、there are more color-blind women than color-blind men
D、failure of rods cause color-blindness
答案
B
解析
转载请注明原文地址:https://kaotiyun.com/show/qJlO777K
0
专业英语八级
相关试题推荐
CyclingawakensmyinnerTrotwood.DavidCopperfield’sgreat-auntBetseywasobsessedwithdonkeystrespassingonthegreenouts
WhatwaseducationlikeinProfessorWang’sdays?
Whatstrikesthewomanmostaboutthemalerobberishis
Accordingtothenews,AmericantroopsinPanama
"littledidtheEnglishpeopleownhimforhisservice"(paragraphone)meansthattheEnglish______.Therelationshipbetween
FewmoderntravelwritersexcitemorehostilityandawethanSirWilfredThesiger,whodiedin2003.Despisingthe"drabuniform
Insixteenth-centuryItalyandeighteenth-centuryFrance,waningprosperityandincreasingsocialunrestledtherulingfamilies
Insixteenth-centuryItalyandeighteenth-centuryFrance,waningprosperityandincreasingsocialunrestledtherulingfamilies
Whennatureisleftalone,abalanceisreachedamongtheanimalsandplantslivinginonearea.Butwhenmaninterfereswithna
Theold-agepaternalismofsouthernCanadiansoverEskimoshasdiedmoreslowlyintheruralvillageswhereEskimoshavebeenmo
随机试题
用碳素钢制造的压力容器焊后不需要热处理。
个人所得税法对每项应税所得的费用扣除范围和标准作了哪些规定?
Itdoesn’tmatterwhenorhowmuchapersonsleeps,buteveryoneneedssomeresttostayalive.That’swhatalldoctorsthought,
男性,41岁,因外伤后感染,发生了气性坏疽,下列哪项处理措施最重要()
(2008年)在单缝夫琅禾费衍射实验中,屏上第三级明纹对应的缝问的波振面,可划分为半波带数目为()个。
根据税收征收管理法律制度的规定,纳税人办理停业、复业登记的,其停业期限不得超过()。
甲企业位于市区,2018年3月1日转让一处2015年6月1日购置的位于市区的仓库,其购置和转让情况如下:(1)2015年6月1日购置该仓库时取得的发票上注明的价款为525万元,另支付契税款20万元并取得契税完税凭证。(2)由于某些原因在转让仓库时未
以淄博齐国故城、殉马坑、蒲松龄故居为主体的齐文化旅游区是山东旅游特色线路之一。()
下列与婴儿生长发育特点不符合的是()。
WELCOMEWelcometoWindsorCastle,theoldestandlargestoccupiedcastleintheworld.Windsorisoneoftheofficialresi
最新回复
(
0
)