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 to 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 determined by pigment cells, which contain melanin (黑色素). The number, size and darkness of melanin per pigment 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 pigmented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebrafish genes.
Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun (太阳光紫外线), which can cause skin cancer.
But when modern humans leave Africa to live in northern 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. It also could lead to research into ways to change skin color without damaging it like chemical treatment did on Michael Jackson. The passage mainly tells us that ________.
| A．people can not change their skin color without any pain |
| 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．scientists have found out that people’s skin color is determined by the gene |
It can be inferred from the passage that ________.
| A．nowadays people who want to change their skin color have to suffer a 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 |
Scientists have done an experiment on a dark-striped zebrafish in order to ________.
| A．find the different genes of 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．find out the ways of changing people’s skin color |
The reason why Europeans are light-skinned is probably that _____
| A．they are born 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 towards the discovery is ________.
| A．neutral（中立的） | B．negative | C．positive | D．indifferent（冷漠） |
New Zealand
【What can you see? Mountains, volcanoes, rivers, lakes, waterfalls, forests, beaches. Both islands are mountainous. In fact, only 30% of New Zealand is flat.】
The Maoris
When the Maoris first arrived in New Zealand, they lived in villages and were excellent fishermen, hunters and farmers. About 50 years ago many Maoris started to live and work in the large cities and took jobs in government, industries, medicine and education. They are proud of their culture and are determined to keep many of the customs which are part of their way of life.
Who can you meet? Most people live on North Island. Eighty-five percent of New Zealanders are “pakeha” (“white men”), which means their “great grandfathers” came from Europe. Ten percent are Maoris. The Maoris came to New Zealand from the Polynesian islands probably around the tenth century. The “pakeha” started to arrive in New Zealand from Europe about 200 years ago as farmers and traders.
Fact box: New Zealand
Position: South of the Equator ;
Nearest neighbor: Australia, 1600 km away.
Size: Two main islands — North Island and South Island: together they are 268.680 sq. km.
Population: 4 million
Capital: Wellington
Languages: English and Maori
| A．20% of the population being Maoris. |
| B．Four million white people. |
| C．About 1600 km south of the Equator. |
| D．Nearly 1/3 of the country being plains. |
| A．1000 years ago. | B．200 years ago. |
| C．85 years ago. | D．50 years ago. |
| A．Living in small villages. | B．Developing farming skills. |
| C．Keeping their own culture. | D．Taking up government jobs. |
When Frida Kahlo’s paintings were on show in London, a poet described her paintings as “a ribbon (丝带)around a bomb”. Such comments seem to suggest Kahlo had a big influence on the art world of her time. Sadly, she is actually a much bigger name today than she was during her time.
Born in 1907 in a village near Mexico City, Kahlo suffered from polio (小儿麻痹症)at the age of seven. Her spine (脊柱)became bent as she grew older. Then, in 1925, her back was broken in several places in a school-bus accident. Throughout the rest of her life, the artist had many operations, but nothing was able to cure the terrible pain in her back. However, the accident had an unexpected side effect. While lying in her bed recovering, Kahlo taught herself to paint.
In 1929, she got married to Diego Rivera, another famous Mexican artist. Rivera’s strong influence on Kahlo’s style can be seen in her early works, but her later works from the 1940s, known today as her best works, show less influence from her husband.
Unfortunately, her works did not attract much attention in the 1930s and 1940s, even in her home country. Her first one-woman show in Mexico was not held until 1953.For more than a decade after her death in 1954, Kahlo’s works remained largely unnoticed by the world, but in the 1970s her works began to gain international fame at last.
| A．a far better artist |
| B．a far more gifted artist |
| C．a much stronger person |
| D．a much more famous person |
| A．polio | B．her bent spine |
| C．back injuries | D．the operations she had |
| A．1930s | B．1940s |
| C．1950s | D．1970s |
| A．Devotion | B．Sympathy |
| C．Worry | D．Encouragement |
Some years ago, writing in my diary used to be a usual activity. I would return from school and spend the expected half hour recording the day’s events, feelings, and impressions in my little blue diary. I did not really need to express my emotions by way of words, but I gained a certain satisfaction from seeing my experiences forever recorded on paper. After all, isn’t accumulating memories a way of preserving the past?
When I was thirteen years old, I went on a long journey on foot in a great valley, well-equipped with pens, a diary, and a camera. During the trip, I was busy recording every incident, name and place I came across. I felt proud to be spending my time productively, dutifully preserving for future generations a detailed description of my travels. On my last night there, I wandered out of my tent, diary in hand. The sky was clear and lit by the glare of the moon, and the walls of the valley looked threatening behind their screen of shadows. I automatically took out my pen...
At that point, I understood that nothing I wrote could ever match or replace the few seconds I allowed myself to experience the dramatic beauty of the valley. All I remembered of the previous few days were the dull characterizations I had set down in my diary.
Now, I only write in my diary when I need to write down a special thought or feeling. I still love to record ideas and quotations that strike me in books, or observations that are particularly meaningful. I take pictures, but not very often—only of objects I find really beautiful. I’m no longer blindly satisfied with having something to remember when I grow old. I realize that life will simply pass me by if I stay behind the camera, busy preserving the present so as to live it in the future.
I don’t want to wake up one day and have nothing but a pile of pictures and notes. Maybe I won’t have as many exact representations of people and places; maybe I’ll forget certain facts, but at least the experiences will always remain inside me. I don’t live to make memories—I just live, and the memories form themselves.
| A．observing her school routine |
| B．expressing her satisfaction |
| C．impressing her classmates |
| D．preserving her history |
| A．A dull night on the journey. |
| B．The beauty of the great valley. |
| C．A striking quotation from a book. |
| D．Her concerns for future generations. |
| A．Notes and beautiful pictures. |
| B．Special thoughts and feelings. |
| C．Detailed accounts of daily activities. |
| D．Descriptions of unforgettable events. |
| A．to experience it |
| B．to live the present in the future |
| C．to make memories |
| D．to give accurate representations of it |
Every year Chris Brogan posts his three words for a new year. Many others and I have followed his lead for the past three or four years. They helped me a lot. My words for last year were “passion”, “focus” and “delegate” and I stayed true to them. This year, 2013, my goals are more personal and less professional.
FOCUS
Focus is making a repeat appearance on my list this year because I’m too much of a multitasker. The problem is that I have trouble finishing one thing with so many things calling me. When I was working as a writer, all my projects were handled via a schedule, I’m putting a fitness and housekeeping routine into my schedule.
HEALTH
I get so busy taking care of everyone else, and I forget to take care of myself and this has to change. My health suffers and my weight suffers. I have to get my health in check, not only for me but because I promised my 9-year-old son. I’ll make good food and lifestyle choices. I miss being thin, and it’s time to get it back.
CELEBRATE
What good is having it if I’m not taking time to enjoy it? I have a wonderful job, a happy family, and so much to be thankful for. So how come I spend all my time working? Last summer my family took our first vacation in four years, the best thing I’ve done for myself and my family in a long time. This year, I’m making sure to take time to enjoy life and celebrate its many blessings.
Do you have any words for 2014?
| A．makes a living by writing |
| B．always fails to finish a task on time |
| C．has several things to do at the same time |
| D．pays more attention to fitness and housekeeping |
| A．He wants to take better care of others. |
| B．He’s gaining weight and feeling bad. |
| C．He did not take any exercise in the past. |
| D．He got the idea from his son. |
| A．The word “CELEBRATE” can remind the writer to enjoy life. |
| B．The writer has a vacation with his family every four years. |
| C．The word “FOCUS” can help the writer focus on his family. |
| D．The writer used to be overweight for lack of exercise. |
While students in Yinchuan are quite used to clear skies, Beijing teenagers are not so lucky. As another warm winter approaches, the city can expect the normal clouds of smoke caused by air pollution.
But things may start to improve soon. The government is co-operating with a US-based environmental protection agency to update existing buses and trucks with clean fuel technology. The new technology could reduce air pollutants in existing diesel engines(柴油机)by 40 percent. The programme will begin by testing buses in Beijing to see if the technology can be applied to them.
“We encourage the development of public transports. But at the same time we need to reduce pollution from them, ”said an official.
Efforts are being made to improve the capital’s environment with tighter controls on emissions(排放). Some heavily polluting factories and construction sites, such as those owned by the steel giant Shougang Group, have been asked to cut production in November and December or be closed.
Beijing was the third polluted city in the world at the end of last century, according to the UN. But thanks to recent measures, the capital has made some progress. Last year 224 clear days were rated as having good air quality. In 1998 the air quality index(指数)gave just 100 days as good.
“I am glad to see an improvement, ”said a senior 1 boy living in the northwest of Beijing. “Compared to other places, the air quality of Beijing is still worrying though. I hate pollution. Once I was riding my bike in the morning when I almost had a traffic accident because I couldn’t see a car only metres away from me in fog. ”
In early October, the skies were covered by such a thick fog that a display show by the visiting French Air Force was called off.
Rapid development, industry, traffic fumes and sandstorms from the desert all contribute to the city’s bad air.
| A．a programme aiming at improving Beijing’s air quality |
| B．progress made in Beijing’s air quality |
| C．Beijing’s air pollution |
| D．the differences between Yinchuan and Beijing |
| A．Clean fuel technology will be used in public transports. |
| B．Some factories have been asked to cut production. |
| C．Some construction sites have been told to be closed. |
| D．A display show of airplanes has been called off. |
| A．far more still needs to be done |
| B．nothing else needs to be done |
| C．all traffic has to be closed |
| D．the development of the city has to be slowed down |
| A．Beijing’s air quality is getting worse and worse. |
| B．Rapid development, industry, traffic fumes and sandstorms are all the causes of bad air quality. |
| C．People see clouds of smoke in the sky in the winter of Beijing. |
| D．The government is making efforts to stop air pollution. |
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