Question

【題目】 The fact that your hair turns grey because of stress is nothing more than an old wives' tale. It's true that stress isn't good for you, but it's not going to turn you into a silver fox just yet. In fact, the answer comes from the cells in your hair. These are what decide the color and, eventually, the fade to grey.

Most of us start to notice our first grey hairs by the time we hit our thirties. A general rule to go by is that by the age of 50, half of the population will have lost the color in 50 percent of their hair.

But why does it happen? Firstly, we need to understand how hair gets its color.

Your hair is made up of cells called melanocytes (黑色素細(xì)胞) which produce pigments (色素) as they grow into the hair fiber. There are two different types of melanins: eumelanins and pheomelanins. The former produces black and brown pigments, while the latter produces red and yellow pigments. The exact amount of these pigments decide whether a person has black, brown, blonde or red hair.

As we age, the ability of the melanocytes to produce more pigments weakens. That's because our hair grows in different periods.

The growing period lasts between three and five years, after which our follicles (毛囊) turn off for about three months to rest and get ready to grow more hairs. This goes round and round and, after a time, our bodies aren't as good at producing new hairs.

Scientists are continuing to try and find ways to prevent greying hair. A team of scientists in France is working to try and stop the melanocytes from being damaged at the end of each hair cycle. They are trying to use a special enzyme (酶) to protect the cells from damage. If successful, it could lead the way for new products that keep our hair full of color for years to come.

【1】What does the phrase 'an old wives' tale' in Paragraph 1 probably mean?

A.A wrong beliefB.A useful talk

C.A scientific ruleD.A helpful experience

【2】What do we know about red hair?

A.It doesn’t turn grey as people get older.

B.It contains more pheomelanins than eumelanins.

C.The amount of pigments in it doesn't change over time.

D.People with red hair have weaker ability to produce pigments.

【3】What do the French scientists aim to do?

A.To repair damaged hair follicles.

B.To protect hair cells against damage.

C.To shorten the hair cycle to protect the hair.

D.To study the relationship between health and hair color.

【4】What can be a suitable title for the text?

A.Grey Hair: a Symbol of Huge Pressure.

B.Grey Hair: a Symbol of Declining Health.

C.Cells: the Cause of New Hair Growth.

D.Cells:the Cause of Color Change of Hair.

Answer 1

【答案】

【1】A

【2】B

【3】B

【4】D

【解析】

這是一篇說(shuō)明文。文章主要講述了研究發(fā)現(xiàn)決定我們頭發(fā)顏色的是頭發(fā)里面的兩種色素細(xì)胞：真黑色素和黑色素，前者生產(chǎn)黑色和棕色，后者產(chǎn)生紅色和棕色。科學(xué)家們發(fā)現(xiàn)，只要保證色素細(xì)胞不受到損害，頭發(fā)就不會(huì)變白。

【1】

詞義猜測(cè)題。根據(jù)第一段的The fact that your hair turns grey because of stress is nothing more than an old wives' tale. It's true that stress isn't good for you, but it's not going to turn you into a silver fox just yet.可知，你的頭發(fā)是因?yàn)閴毫Χ�變白的，這種說(shuō)法只不過(guò)是an old wives' tale。壓力對(duì)你沒(méi)有好處這是對(duì)的，但也不會(huì)把你變成一頭銀發(fā)。根據(jù)句意推測(cè)劃線部分的意思是“不正確的說(shuō)法/無(wú)稽之談”。A. A wrong belief(一個(gè)錯(cuò)誤的信念)符合以上說(shuō)法，故選A項(xiàng)。

【2】

推理判斷題。根據(jù)第四段的There are two different types of melanins: eumelanins and pheomelanins. The former produces black and brown pigments, while the latter produces red and yellow pigments. The exact amount of these pigments decide whether a person has black, brown, blonde or red hair.(黑色素有兩種不同的類型：真黑色素和黑色素。前者產(chǎn)生黑色和棕色色素，后者產(chǎn)生紅色和黃色色素。這些色素的量決定了一個(gè)人是黑色、棕色、金色還是紅色的頭發(fā))可推測(cè)，如果頭發(fā)是紅色，它含有的黑色素就比真黑色素多。B. It contains more pheomelanins than eumelanins.(比起真黑色素來(lái)它含有更多的黑色素)符合以上說(shuō)法，故選B項(xiàng)。

【3】

細(xì)節(jié)理解題。根據(jù)最后一段的A team of scientists in France is working to try and stop the melanocytes from being damaged at the end of each hair cycle. They are trying to use a special enzyme (酶) to protect the cells from damage.(法國(guó)的一個(gè)科學(xué)家團(tuán)隊(duì)正在努力阻止黑色素細(xì)胞在每次發(fā)絲周期結(jié)束時(shí)受損。他們?cè)噲D用一種特殊的酶來(lái)保護(hù)細(xì)胞不受傷害)可知，法國(guó)科學(xué)家致力于保護(hù)頭發(fā)細(xì)胞不受傷害。B. To protect hair cells against damage.(為了保護(hù)頭發(fā)細(xì)胞不受傷害)符合以上說(shuō)法，故選B項(xiàng)。

【4】

主旨大意題。根據(jù)文章的主要內(nèi)容，尤其是第四段的Your hair is made up of cells called melanocytes (黑色素細(xì)胞) which produce pigments (色素) as they grow into the hair fiber. There are two different types of melanins: eumelanins and pheomelanins. The former produces black and brown pigments, while the latter produces red and yellow pigments. The exact amount of these pigments decide whether a person has black, brown, blonde or red hair.(你的頭發(fā)是由黑色素細(xì)胞構(gòu)成的，在長(zhǎng)成頭發(fā)纖維的過(guò)程中它們可以生產(chǎn)色素。黑色素有兩種不同的類型：真黑色素和黑色素。前者產(chǎn)生黑色和棕色色素，后者產(chǎn)生紅色和黃色色素。這些色素的量決定了一個(gè)人是黑色、棕色、金色還是紅色的頭發(fā))可知，本文主要講述了決定我們頭發(fā)顏色的是頭發(fā)里面的黑色素細(xì)胞，如果能讓它們不受到損害，我們的頭發(fā)就不會(huì)變白。D. Cells:the Cause of Color Change of Hair.(細(xì)胞：頭發(fā)改變顏色的原因)可以作為本文標(biāo)題，故選D項(xiàng)。