6.Does stress cause gray hair?Many people believe that tension and stress can cause your hair to lose its color.In fact,it is an old wives tale that being upset all the time can result in premature graying.Here is a closer look at this situation and why some believe that this old wives tale could be true.
As one ages,the hairs on the head also age.In fact,just about everything on the human body begins to show signs of wear and tear after a while.The joints wear become stiff and skin wears and becomes wrinkled.Hairs on the head grow and eventually die.They are replaced,but in the process something else happens.
When new hairs are replaced,the color or pigment(色素)is also added to them.However,as one ages,this pigment becomes less and less available.At first,hairs will have a limited amount of pigment and they will appear to be grayish in color.In time,they will lose all of their pigment and will be white.Many things are known to cause graying and genetics is a very powerful factor.If one of your parents turns gray at an early age,there is a good chance that you will too.Some people begin the graying process in high school,while others may be over the age of forty.
Constant worry and tension can have many harmful effects on the human body.It is a known fact that stressful times can cause one to suffer hair loss.It would make sense that if it can cause these problems,perhaps it also may contribute to graying.However,there is no sound evidence to support this.
On the other hand,many medical professionals believe that there may be a link:between graying and a constant state of anxiety or tension.Does stress cause gray hair?There is no scientific evidence to support the theory,but it is best to avoid stressful situations.
24.The underlined phrase in the first paragraph most probably meansA.
A.silly remarks
B.clever remarks
C.exciting remarks
D.disappointed remarks
25.The second paragraph mainly tells usC.
A.every part of body is replaced with age
B.hairs will grow weak but not die
C.every part of body ages with age
D.skin becomes wrinkled with age
26.From the passage we can infer thatD.
A.sound evidence has been found.
B.gray hair has nothing to do with tension.
C.stressful situations can be of benefit.
D.stress causing gray hair is still in question.
27.What might play the most important role in the graying process?B
A.Genetics and the amount of sleeping time.
B.The amount of pigment and genetics.
C.The amount of food people eat and living environment.
D.Genetics and the amount of water people drink.
分析 本文就一個問題(壓力會導(dǎo)致頭發(fā)變白嗎)展開了論述.很多人相信壓力會使頭發(fā)變白.文章從年齡和基因兩方面談?wù)摿祟^發(fā)變白的原因.持續(xù)的壓力和憂慮對身體是有害的,可導(dǎo)致脫發(fā).但究竟壓力和頭發(fā)變白之間是否有聯(lián)系,目前尚無科學(xué)的證據(jù).
解答 24.A詞義猜測題.根據(jù)第一段"Many people believe that tension and stress can cause your hair to lose its color."可知許多人認為緊張和壓力會導(dǎo)致頭發(fā)褪色變白.文章接下來談到"In fact,it is…"以及下文可知,這種論斷是沒有科學(xué)依據(jù)的.由此可知,"an old wives tale"是指不經(jīng)之談或不科學(xué)的陳腐思想.故選A.
25.C主旨大意題.根據(jù)第二段As one ages,the hairs on the head also age.In fact,just about everything on the human body begins to show signs of wear and tear after a while.可知人體的每一部分都會隨著年齡的增長而衰老.C選項恰當(dāng)?shù)馗爬嗽摱蔚拇笠猓蔬xC.
26.D推理判斷題.根據(jù)倒數(shù)第二段However,there is no sound evidence to support this.以及最后一段"There is no scientific evidence to support the theory…",可知壓力是否會引起頭發(fā)變白尚無定論.故選D.
27.B細節(jié)理解題.根據(jù)第三段"At first,hairs will have a limited amount of pigment and they will appear to be grayish in color.In time,they will lose all of their pigment and will be white.Many things are known to cause graying.a(chǎn)nd genetics is a very powerful factor."可知色素和基因在頭發(fā)變白的過程中起著重要的作用.故選B.
點評 本文考察學(xué)生的理解推斷能力以及細心程度,只要抓住文章的關(guān)鍵詞,采用尋讀的方法查找細節(jié),就能找到正確答案.