Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes.Scientists have found the gene that determines skin color.
The gene comes in two versions, one of which is found in 99 per cent of Europeans.The other is found in 93 t0 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the color of a dark - striped zebrafish(斑马鱼) to uniform gold by inserting a version of the pigment(色素) gene into a young fish.As with humans, zebrafish skin color is deter-mined by pigment cells，which contain melanin(黑色素).The number, size and darkness of melanin perpigment cell determine skin color.
It appears that, like the golden zebrafish, light - skinned Europeans also have a mutation (变异) in the gene for melanin production.This results in less pigrnented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in hu-man ancl zebrafish genes.
Humans acquired dark skin in Africa about l.5 million years ago to protect bodies from ultra - violetrays of the sun. which can cause skin cancer.
But when modem humans leave Africa to live in northem latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.
Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin color, said Cheng.
The new discovery could lead to medical treatments for skin cancer.lt also could lead to research in-to ways to change skin color without damaging it like chemical treatment did on Michael Jackson.Scientists have done an experiment on a dark -striped zebrafish in order to
| A．fincl the different genes o humans' |
| B．prove the humans' skin color is determined by the pigment gene |
| C．find out the reason why the Africans' skin color is dark |
| D．fincl out the ways of changing people's skin color |
lt can be inferred from the passage that .
| A．nowadays people who want to change their skin color have to suffer 8 lot from the damage caused by the chemical treatment |
| B．Europeans and Africans have the same gene |
| C．the new discovery could help to find medical treatments for skin cancer |
| D．there are two kinds of genes |
The passage mainly tells us that .
| A．scientists have found out that people's skin color is determined by the gene |
| B．the new discovery could lead to research into ways to change skin color safely |
| C．pop king Michael Jackson often changed his skin color as he liked |
| D．people can not change their skin color without any pain |
The reason why Europeans are light - skinned is probably that .
| A．they are bom light - skinned people |
| B．light - skinned Europeans have mutation in the gene for melanin production |
| C．they have fewer activities outside |
| D．they pay much attention to protecting their skin |
The writer's attitude towarcls the discovery is .
| A．neutral | B．negative | C．indifferent | D．positive |
It was a winter morning, just a couple of weeks before Christmas 2005. While most people were warming up their ears, Trevor, my husband, had to get up early to ride his bike four kilometers away from home to work. On arrival, he parked his bike outside the back door as he usually does. After putting in 10 hours of labor, he returned to find his bike gone.
The bike, a black Kona 18 speed, was our only transport. Trevor used it to get to work, putting in 60-hour weeks to support his young family. And the bike was also used to get groceries (食品杂货) saving us from having to walk long distances from where we live.
I was so sad that someone would steal our bike that I wrote to the newspaper and told them our story. Shortly after that，several people in our area offered to help. One wonderful stranger even bought a bike, then called my husband to pick it up. Once again my husband had a way to get to and from his job. It really is an honor that a complete stranger would go out of their way for someone they have never met before.
People say that a smile can be passed from one person to another, but acts of kindness from strangers are even more so. This experience has had a spreading effect in our lives because it strengthened our faith in humanity (人性) as a whole. And it has influenced (影响) us to be more mindful of ways we, too, can share with others. No matter how or how small, an act of kindness shows that someone cares. And the results can be everlasting.Why was the bike so important to the couple?
| A．The man’s job was bike racing. | B．It was their only possession. |
| C．It was a nice Kona 18 speed. | D．They used it for work and daily life |
We can infer from the text that ________
| A．The couple worked 60 hours a week | B．people were busy before Christmas |
| C．the stranger brought over the bike | D．life was hard for the young family |
How did people get to know the couple’s problem?
| A．From radio broadcasts. | B．From a newspaper. |
| C．From TV news. | D．From a stranger. |
What do the couple learn from their experience?
| A．Strangers are usually of little help. | B．One should take care of their bike. |
| C．News reports make people famous. | D．An act of kindness can mean a lot. |
The meaning of the word “volunteer ” may be a little different in different countries, but it usually means “one who offers his or her services.” There are many different ways in which people can volunteer, such as taking care of sick people, working in homes for homeless children, and picking up garbage(垃圾) from beaches and parks. Volunteers may work within their own countries or in other countries. They are often people with a strong wish to help those who are less fortunate than themselves. Volunteers don’t expect any kind of pay.
At the root of volunteering is the idea that one person may have the ability to offer services that can help other people. Tracy, a good friend of mine, however, recently came back from India with a new idea of what being a volunteer means. She worked for two and a half weeks in one of Mother Teresa’s homes in Calcutta. The following is her story.
“I first heard about Mother Teresa in my high school, we watched a video(录像) about her work in India and all over the world. I was so moved by her spirit to help others and her endless love for every human being that after I graduated from high school, I too wanted to try her kind of work. So with two friends I flew to Calcutta for a few weeks.”
“I was asked to work in a home for sick people. I helped wash clothes and sheets, and pass out lunch. I also fed the people who were too weak to feed themselves and tried to cheer them up. I felt it was better to share with them than to think that I have helped them. To be honest, I don’t think I was helping very much. It was then that I realized that I had not really come to help, but to learn about and experience another culture(文化) that helped improve my own understanding of life and the world.”According to the text, a volunteer refers to a person who ______.
| A．is willing to help those in need without pay |
| B．can afford to travel to different places |
| C．has a strong wish to be successful |
| D．has made a big fortune in life |
Tracy started her work as a volunteer _______.
| A．after she met Mother Teresa | B．after she finished high school |
| C．when she was touring Calcutta | D．when she was working in a hospital |
Why did Tracy choose to be a volunteer?
| A．She liked to work with Mother Teresa. |
| B．She had already had some experience. |
| C．She was asked by Mother Teresa’s example. |
| D．She wanted to follow Mother Teresa’s example. |
What is Tracy’s “new idea” (Paragraph 2) of being a volunteer?
| A．Going abroad to help the sick. |
| B．Working in Mother Teresa’s home. |
| C．Doing simple things to help the poor. |
| D．Improving oneself through helping others. |
How I Turned to Be Optimistic
I began to grow up that winter night when my parents and I were returning from my aunt's house, and my mother said that we might soon be leaving for America. We were on the bus then. I was crying, and some people on the bus were turning around to look at me. I remember that I could not bear the thought of never hearing again the radio program for school children to which I listened every morning.
I do not remember myself crying for this reason again. In fact, I think I cried very little when I was saying goodbye to my friends and relatives. When we were leaving I thought about all the places I was going to see-—the strange and magical places I had known only from books and pictures. The country I was leaving never to come back was hardly in my head then.
The four years that followed taught me the importance of optimism, but the idea did not come to me at once. For the first two years in New York I was really lost—having to study in three schools as a result of family moves. I did not quite know what I was or what I should be. Mother remarried, and things became even more complex for me. Some time passed before my stepfather and I got used to each other. I was often sad, and saw no end to "the hard times."
My responsibilities in the family increased a lot since I knew English better than everyone else at home. I wrote letters, filled out forms, translated at interviews with Immigration officers, took my grandparents to the doctor and translated there, and even discussed telephone bills with company representatives.
From my experiences I have learned one important rule: almost all common troubles eventually go away! Something good is certain to happen in the end when you do not give up, and just wait a little! I believe that my life will turn out all right, even though it will not be that easy.How did the author get to know America?
| A． From her relatives. | B． From her mother. |
| C． From books and pictures. | D． From radio programs. |
Upon leaving for America the author felt_______.
A. confused B. excited C. worried D amazedFor the first two years in New York, the author _________.
A. often lost her way B. did not think about her future
C. studied in three different schools D got on well with her stepfatherWhat can we learn about the author from Paragraph 4?
A. She worked as a translator. B. She attended a lot of job interviews.
C. She paid telephone bills for her family. D She helped her family with her English.
Last week my youngest son and I visited my father at his new home in Tucson, Arizona. He moved there a few years ago, and I was eager to see his now place and meet his friends.
My earliest memories of my father are a tall, handsome, successful man devoted to his work and family but uncomfortable with his children. As a child I loved him; as a school girl and young adult(成年人)I feared him and felt bitter about him. He seemed unhappy with me unless I got straight A’s and unhappy with my boy friends if their fathers were not as “successful” as he was. Whenever I went out with him on weekends, I used to struggle to think up things to say, feeling on guard.
On the first day of my visit, we went out with one of my father’s friends for lunch at an outdoor cafe. We walked along that afternoon, did some shopping, ate on the street table, and laughed over my son’s funny facial expressions. Gone was my father’s critical(挑剔的)air and strict rules. Who was this person I knew as my father, who seemed so friendly and interesting to be around? What had held him back before?
The next day my dad pulled out his childhood pictures and told me quite a few stories about his own childhood. Although our times together became easier over the years, I never felt closer to him at that moment. After so many years, I’m at last seeing another side of my father. And in so doing, I’m delighted with my new friend. My dad, in his new home in Arizona, is back to me from where he was.Why did the author feel bitter about her father as a young adult?
| A．He was silent most of the time | B．He was too proud of himself |
| C．He did not love his children | D．He expected too much of her |
When the author went out with her father on weekends, she would feel .
| A．nervous | B．sorry | C．tired | D．safe |
What does the author think of her father after her visit to Tucson?
| A．More critical | B．More talkative |
| C．Gentle and friendly | D．Strict and hard-working |
The underlined words “my new friend” in the last paragraph refer to .
| A．the author’s son | B．the author’s father |
| C．the friend of the author’s father | D．the cafe owner |
Most people who live in Seattle, Washington, love their city. There is a never-ending flow of fun things to do. But, people who live there do not always enjoy the day-after-day absence of sunshine during the winter months.
It is documented fact that sunshine (or lack of it) plays a major role in how each of us meets the day. It also affects how we perform at school or work. When people are derived of sunlight, they can develop seasonal affective disorder, which makes it difficult for them to feel happy or get things accomplished. No major city in the United States is more affected by the “sunshine factor” than Seattle.
To fight drizzle and fog during the winter months, Steve Murphy created a business that is very popular among the locals. The Indoor Sun Shoppe is more than a little ray of sunshine during the gray days of Seattle’s winter. His shop offers a huge source of plants and artificial lighting for people who are trying to overcome seasonal affective disorder.
Located in Fremont, Washington, The Indoor Sun Shoppe has an amazing collection of exotic plants and “good bugs” in a humid and well-lit environment. At The Indoor Sun Shoppe, you can spend up to $400 for artificial lighting that will chase away the winter blues. It will also keep your plants healthy. You can buy a dawn simulator that will gradually fill your room with a warming wake-up glow. What better way to meet a Seattle morning when real sunshine is nothing more than a happy thought!
Murphy’s in-home waterfalls are also popular with customers. But his plants and lights remain the “main course.” On a cloudy winter day, The Indoor Sun Shoppe is a bright spot in Seattle!Which of the following statements is NOT TRUE according to the passage?
| A．Seattle is located in the state of Washington. |
| B．Citizens love Seattle for their colorful city lives. |
| C．Sunshine in Seattle is rare during the winter months. |
| D．People who live in Seattle are used to the sunshine absence. |
Which of the following best defines the term seasonal affective disorder in Para.2?
| A．mild temperature and a general feeling of illness caused by gray winter |
| B．exhaustion, depression and lack of energy caused by a lack of sunlight |
| C．winter-related illness caused by the low temperature and little sunlight |
| D．post-holiday depression that comes when relatives leave after Christmas |
The Indoor Sun Shoppe _____.
| A．attracts people from different parts of the whole country |
| B．aims to create a humid and well-lit environment during winter months |
| C．brings only a little ray of sunshine during the gray days of Seattle’s winter |
| D．offers variety of goods helping people overcome seasonal affective disorder |
Which of the following best explains the use of a dawn simulator?
| A．An alarm clock stimulated by the light rays of early morning. |
| B．A bringer of indoor artificial sunshine when there is none outside. |
| C．An automatic waterfall system helping make indoor plants healthy. |
| D．A better way to meet a Seattle morning with real warming sunshine. |
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