About ten men in every hundred suffer from colour blindness in some way; women are luckier only about one in two hundred is affe

admin2011-02-28  30

问题    About ten men in every hundred suffer from colour blindness in some way; women are luckier only about one in two hundred is affected in this manner. There are different forms of colour blindness. A man may not be able to see deep red. He may think that red, orange and yellow are all shades of green. Sometimes a person cannot tell the differenee between blue and green. In rare cases an unlucky man may see everything in shades of green—a strange world indeed.
   In certain occupations colour blindness can be dangerous and candidates are tested most carefully. For example, when fighting at night, soldiers use lights of flares to signal to each other. A green light may mean "Advance" and a red hght may mean "Danger! Keep back!" You can see what will happen if somebody thinks that red is green! Colour blindness in human’ beings is a strange thing to explain. In a single eye there are millions of very small things called "cones". These help to see in a bright light and to tell the difference between colours. There are also millions of "rods" but these are used for seeing when it is nearly dark. They show us shape but not colour. Wait until it is dark tonight, then go outside. Look round you and try to see what colors you can recognize.
   Birds and animals which hunt at night have eyes which contain few or no cones at all, so they cannot see colours. As far as we know, bats and adult owls cannot see colours at all. Similarly cats and dogs cannot see colours as well as we can. Insects can see ultraviolet rays which are invisible to us, and some of them can even see X-rays. The wings of a moth may seem grey and dull to us, but to insects they may appear beautiful, showing colours which we cannot see. Scientists know that there are other colours around us which insects can see but which we cannot see. Some insects have favorite colours. Mosquitoes like blue, but do not like yellow. A red light will not attract insects but a blue tamp will.
Which of the following is not true about insects?

选项 A、Insects can see more colours than human beings.
B、Insects can see ultraviolet rays which are invisible to man.
C、All insects have their favorite colours.
D、The world is more colorful to insects than to human beings.

答案C

解析 关于昆虫的讲述在文中的最后一段中,从叙述中,我们知道,昆虫能看到许多我们人类看不见的颜色,它们所看到紫外线和X射线,这里复数形式“insects”,代表所有昆虫的共有的特征,所以A、B、D的内容都是正确的,C项说所有的昆虫都有它们自己喜爱的颜色,与文中说的一些昆虫有自己喜爱的颜色不符,故为C。
转载请注明原文地址:https://kaotiyun.com/show/Rptd777K
0

随机试题
最新回复(0)