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
Right and Left-handedness in Humans Why do humans, quite different from the other animal species, display a distinct left or
Right and Left-handedness in Humans Why do humans, quite different from the other animal species, display a distinct left or
admin
2010-05-26
55
问题
Right and Left-handedness in Humans
Why do humans, quite different from the other animal species, display a distinct left or right handedness? Not even our closest relatives among the apes(猿) possess such decided lateral(横向的,侧面的) asymmetry(不对称), as psychologists call it. Yet about 90 per cent of every human population that has ever lived appears to have been right-handed. Professor Bryan Turner at Deakin University has studied the research literature on left-handedness and found that handedness goes with sidedness. So nine out of ten people are right-handed and eight are right-footed. He noted that this distinctive asymmetry in the human population is itself systematic. "Humans are able to think about things in categories: black and white, up and down, left and right, It’s a system of signs that enables us to categorize phenomena that are essentially ambiguous."
The Relationship of Handedness to Gene and Inheritance
Research has shown that there is genetic or inherited(遗传的) element to bandedness. But while left-handedness tends to appear in families, neither left nor right handers will automatically produce children with the same handedness; in fact about 6 per cent of children with two right-handed parents will be left-handed. However, among two left-handed parents, perhaps 40 per cent of the children will also be left-handed. With one right and one left-handed parent, 15 to 20 per cent of the children will be left-handed. Even among identical twins who have exactly the same genes, one in six pairs will differ in their handedness.
Researchers Turned to the Brain for Reasons
while anything on the left is dangerous or even evil. We speak of left-handed advantages, and on the other hand according to Moore, "it is certain that left-handers often develop a stammer(口吃) as they are robbed of their freedom of speech." However, as more research is undertaken on the causes of left handedness, attitudes towards left-handed people are gradually changing for the better. Indeed when the champion tennis player Ivan Lend was asked what the only factor had improved his game, he said he would like to become a left-hander.
Geoff Maslen (Adapted)
With two left-handed parents, about ______ per cent of children will be right-handed.
选项
答案
60
解析
从“However, among two left-handed parents, perhaps 40 per cent of the children will also be left handed.”可以看出双亲都是左手习惯者,那么子女出现左手习惯的机率是40%,则出现左手习惯者子女的几率是60%。
转载请注明原文地址:https://kaotiyun.com/show/m6V7777K
0
大学英语四级
相关试题推荐
Dogsaresocialanimalsandwithoutpropertraining,theywillbehaveaswildanimals.Theywillsoilyourhouses,【M1】_
Educationistooimportanttotake【B1】______.Whenpeopletakeanythingtooseriously,theyputonblinders,whichcausethemto
A、Abusinesscorporation.B、Theuniverseasawhole.C、Asocietyoflegalprofessionals.D、Anassociationofteachersandschola
A、Awriter.B、Alawyer.C、Areporter.D、Ateacher.C
Everyoneshould______(有资格享受)standardoflivingandanopportunitytobeeducation.
A、Itwasprettygood.B、Itwasratherdull.C、Itwasnotwellorganized.D、Itwasattendedbymanypeople.C
A、Sunday.B、Saturday.C、Friday.D、Thursday.C此题为数字题,涉及的是日期。对话中提到今天是星期三,杂志可能后天才会到。稍加计算便可得知答案应当是星期五。
TheAmericaneconomicsystemisorganizedaroundabasicallyprivate-enterprise,market-orientedeconomyinwhichconsumerslarg
TheAmericaneconomicsystemisorganizedaroundabasicallyprivate-enterprise,market-orientedeconomyinwhichconsumerslarg
随机试题
子宫内膜癌首选的治疗方法是()
临床用于治疗消化性溃疡,属于奥美拉唑(–)–(S)–异构体的药物是()。
以下做法不符合相关法律规定的是()
下列倒装句中属于定语后置的一项是()。
在教学中,通过学生观察所学事物或教师语言的形象描述,引导学生形成所学事物、过程的清晰表象,丰富他们的感性认识,从而使他们能够正确地理解书本知识和发展认知能力。这体现的教学原则是()
在CPU中,常用来为ALU执行算术逻辑运算提供数据并暂存运算结果的寄存器是_______。
Awebcamisadigitalcamerathatsendsvideoimagestoothercomputerusers.It’saboutthe【C1】______ofagolfballandtyp
Theoriginsofbottledwatercanbe【B1】______backtotheearliest【B2】______.Wellawareofwater’shealthfacts,theRomansse
Theproblemofhowhealth-careresourcesshouldbeallocatedorapportioned,sothattheyaredistributedinboththemostjust
CanTonyBlairSavetheWorldofBooks?[A]AtthebeginningofAJourney,TonyBlairboaststhathehas"thesoulofarebel".
最新回复
(
0
)