Question

【题目】 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 (黑色素细胞) 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】

这是一篇说明文。文章主要讲述了研究发现决定我们头发颜色的是头发里面的两种色素细胞：真黑色素和黑色素，前者生产黑色和棕色，后者产生红色和棕色。科学家们发现，只要保证色素细胞不受到损害，头发就不会变白。

【1】

词义猜测题。根据第一段的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，你的头发是因为压力而变白的，这种说法只不过是an old wives' tale。压力对你没有好处这是对的，但也不会把你变成一头银发。根据句意推测划线部分的意思是“不正确的说法/无稽之谈”。A. A wrong belief(一个错误的信念)符合以上说法，故选A项。

【2】

推理判断题。根据第四段的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.(黑色素有两种不同的类型：真黑色素和黑色素。前者产生黑色和棕色色素，后者产生红色和黄色色素。这些色素的量决定了一个人是黑色、棕色、金色还是红色的头发)可推测，如果头发是红色，它含有的黑色素就比真黑色素多。B. It contains more pheomelanins than eumelanins.(比起真黑色素来它含有更多的黑色素)符合以上说法，故选B项。

【3】

细节理解题。根据最后一段的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.(法国的一个科学家团队正在努力阻止黑色素细胞在每次发丝周期结束时受损。他们试图用一种特殊的酶来保护细胞不受伤害)可知，法国科学家致力于保护头发细胞不受伤害。B. To protect hair cells against damage.(为了保护头发细胞不受伤害)符合以上说法，故选B项。

【4】

主旨大意题。根据文章的主要内容，尤其是第四段的Your hair is made up of cells called melanocytes (黑色素细胞) 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.(你的头发是由黑色素细胞构成的，在长成头发纤维的过程中它们可以生产色素。黑色素有两种不同的类型：真黑色素和黑色素。前者产生黑色和棕色色素，后者产生红色和黄色色素。这些色素的量决定了一个人是黑色、棕色、金色还是红色的头发)可知，本文主要讲述了决定我们头发颜色的是头发里面的黑色素细胞，如果能让它们不受到损害，我们的头发就不会变白。D. Cells:the Cause of Color Change of Hair.(细胞：头发改变颜色的原因)可以作为本文标题，故选D项。