题目内容

In a study published in the U. S. journal Science, researchers from the Chinese Academy of Agricultural Sciences(CAAS) and the University of Florida identified the chemical combinations and genetic recipe for better tomato flavor(味道).

“In recent years, consumers often complain that the modern tomato is less flavorful than it once was” said co-principal researcher Sanwen Huang. “Our results provide a practical road map for breeding tomato varieties with better flavor.”

For the study, a 170-person consumer group was created to evaluate 160 tomatoes representing 101 varieties, based on qualities such as “overall liking” and “flavor degree”. The results pointed to dozens of chemical compounds of interest, and further research using a statistical model discovered 33 flavor compounds connected with consumer liking, such as glucose(葡萄糖). The reason why modern tomatoes don’t taste good anymore is that a total of 13 of these flavor-associated compounds “were significantly reduced in modern varieties,” their paper wrote. Moreover, the researchers found that smaller fruit tended to have greater sugar content, suggesting that “selection for more sizable tomatoes has cost sweetness and flavor”.

Based on this knowledge, Huang and Professor Harry Klee of the University of Florida studied the whole genomes of 398 varieties of tomato, identifying about 250 positions of genes on a chromosome(染色体), which controlled tomato flavor.

“We’re just fixing what has been damaged over the last half century to push them back to where they were a century ago,” said Klee in a statement. “We can make the supermarket tomato taste noticeably better.” Klee said new tomato varieties with better flavor could be ready in three to four years. In addition, “the genes and pathways identified here in the tomato almost certainly point to pathways worth researching for improvement of flavor quality in other fruit crops,” they wrote.

1.According to the text, the study ________.

A. was carried out just through a survey

B. was conducted by Chinese researchers themselves

C. was completely focused on the genes of different tomatoes

D. was done with the background of declining flavor of tomatoes

2.The researchers have found that ________ in the study.

A. bigger tomatoes are much sweeter

B. some genetic positions affect the taste of tomatoes

C. some chemical compounds make tomatoes less tasty

D. a total of 13 flavor-associated compounds make tomatoes appealing in taste

3.What is the influence of the study according to the text?

A. The study lays the foundation for further researches to improve other fruit crops’ flavor.

B. The study makes it possible for us to have noticeably more tasty tomatoes next year.

C. The study provides a road for where to plant tomatoes with better flavor.

D. The study has fixed all the genes of existing tomatoes.

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It was not until I was 9 years old that I found out my father was ill. It was 1994, but I can remember my mother's words as if it were yesterday: "Kernel, I don't want you to take food from your father, because he has AIDS. Be very careful when you are around him." AIDS wasn't something we talked about in my country when I was growing up. From then on, I knew that this would be a family secret. My parents were not together anymore, and my dad lived alone. For a while, he could take care of himself. But when I was 12, his condition worsened. My father's other children lived far away, so it fell to me to took after him.

We couldn't afford all the necessary medicine for him, and because Dad was unable to work, I had no money for school supplies and often couldn't even buy food for dinner. I would sit in class feeling completely lost, the teacher's words muffled as I tried to figure out how I was going to manage. I did not share my burden with anyone. I had seen people reacted to AIDS. Kids laughed at classmates who had parents with the disease. And even adults could be cruel. When my father was moved to the hospital, the nurses would leave his food on the bedside even though he was too weak to feed himself.

I had known that he was going to die, but after so many years of keeping his condition a secret, I was completely unprepared when he reached his final days. Sad and hopeless, I called a woman at the nonprofit National AIDS Support. That day, she kept me on the phone for hours. I was so lucky to find someone who cared. She saved my life.

I was 15 when my father died. He took his secret away with him, having never spoken about AIDS to anyone, even me. He didn't want to call attention to AIDS. I do.

1.What does Kernel tell us about her father?

A. He had stayed in the hospital since he fell ill.

B. He worked hard to pay for his medication.

C. He told no one about his disease.

D. He was carefully attended by the nurses on his deathbed

2.What can we learn from the underlined sentence?

A. Kernel found what the teacher said hard to understand.

B. Kernel had special difficulty in hearing.

C. Kernel was too tired to hear her teacher's words.

D. Kernel was too troubled to focus on the lesson.

3.Why did Kernel keep her father's disease a secret?

A. She wanted to obey her mother.

B. She was afraid of being looked down upon.

C. She found no one willing to listen to her.

D. She thought it was shameful to have AIDS.

4.What’s the author’s purpose in writing the text?

A. To tell people about the sufferings of her father

B. To prove how little people knew about AIDS.

C. To draw people’s attention to AIDS.

D. To recall a hard time of her childhood.

For Canadians, backpacking Europe is a special ceremony signifying a new life stage. Unlike package tours, backpacking is a struggle, full of discovery and chance connections. It is about focusing on something different from our own lives and losing ourselves in a new world, if only for a moment.

Well, that's what backpacking Europe is supposed to do. That’s what it used to do before modern communications, social media, and commercial hostelling (旅社). Older Canadians would not recognize the Europe that they backpacked in the 1960s, 1970s and even the 1980s. Far from a rough adventure into foreign cultures, the European experience has been shattered in part by today's technology.

A few years ago, I took my then 60-year-old father on a backpacking trip across part of Europe and Turkey. As he is an experienced traveler and someone who possesses a strong sense of adventure, I decided that we'd travel on a budget, staying in hostel dorms. For him, backpacking through Europe in 1969 was about independence and struggle. But two things surprised him at the end of our journey. First was how technology-based backpacking had become: Young people were so directly connected to home that they were hardly away in any meaningful sense. Second, the lack of connections we made with locals. Instead of making us feel closer to a place, he found commercial hostelling actually made us more alienated (疏远的).

But there was some room for hope. While technology takes our attention away from the beauty and history before us, there were also ways in which it helped us to connect with our surroundings. Websites like Airbnb have made it easier to stay with enthusiastic locals. Couch Surfing helps organize meet-ups between locals and travelers. The online marketplace Dopios offers a chance to meet locals through enjoyable experiences like a personalized city tour.

Backpacking can never be the way it was for our parents’ generation. But doing a little study of history and culture before leaving, and bravely getting rid of any electronic devices while traveling, will help give young travelers a taste of the glory days.

1.The underlined word “shattered” in Paragraph 2 most probably means ________.

A. broadened B. relived C. ruined D. acquired

2.After the recent backpacking trip in Europe, the author’s father finds ________.

A. backpackers connect less with locals than before

B. young people dislike getting in touch with their family

C. a hostel is a nice place for travelers to meet each other

D. backpacking in Europe becomes more difficult than before

3.What’s the author’s attitude towards technology?

A. Negative. B. Objective. C. Uncertain. D. Uninterested.

4.The text mainly discusses the relationship between ________.

A. adventures and cultures B. technology and traveling

C. young people and their family D. Canadian travelers and Europeans

The Cambridge Science Festival Curiosity Challenge

Dare to Take the Curiosity Challenge!

The Cambridge Science Festival (CSF) is pleased to inform you of the sixth annual Curiosity Challenge. The challenge invites, even dares school students between the ages of 5 and 14 to create artwork or a piece of writing that shows their curiosity how it inspires them to explore their world.

Students are being dared to draw a picture, write an article, take a photo or write a poem that shows what they are curious about. To enter the challenge, all artwork or pieces of writing should be sent to the Cambridge Science Festival, MIT Museum, 265 Mass Avenue, Cambridge 02139 by Friday, February 8th.

Students who enter the Curiosity Challenge and are selected as winners will be honored at a special ceremony during the CSF on Sunday, April 21st. Guest speakers will also present prizes to the students. Winning entries will be published in a book. Student entries will be exhibited and prizes will be given. Families of those who take part will be included in the celebration and brunch will be served.

Between March 10th and March 15th, eac h winner will be given the specifics of the closing ceremony and the Curiosity Challenge celebration. The program guidelines and other related information are available at: http:// cambridgesciencefestival.org.

1.Who can take part in the Curiosity Challenge?

A. School students. B. Cambridge locals.

C. CSF winners. D. MIT artists.

2.When will the prize-giving ceremony be held?

A. On February 8th. B. On March 10th.

C. On March 15th. D. On April 21st.

3.What type of writing is this text?

A. An exhibition guide. B. An art show review.

C. An announcement. D. An official report.

Flight cancellations(取消) and loss of luggage can ruin even the best-planned holiday. The key to a stress-free trip is having a backup plan.

Fly non-stop. The worst problems involve connections, so it is important to take non-stop flights whenever possible. If you do have to make a connection, try to route through a southern city, where snowstorms and de-icing delays will be less likely. Always allow at least two to three hours for flight connections.

Check the weather. Check the weather in your connecting city, not just the arrival and departure city. If your departure flight is cancelled because of weather, you can go home or back to your hotel. Airlines promise to get you on the next available flight, not the next flight. That could be several days later on a sold-out holiday weekend.

Go early. The earlier in the day you fly, the better your chance of getting rebooked the same day after a missed connection. It will also put you ahead of stranded(滞留的) passengers who arrive later.

Rebook immediately. As soon as your flight is delayed or cancelled, get on the phone and rebook your flight instead of waiting at the ticket counter. If your rebooking is delayed, call or ask your travel agent to find a seat on another carrier, and then ask your original carrier to endorse your ticket to the new airline. Airlines are not required to do this but often do. Learn more at www. dot. gov/ airconsumer/ fly-rights.

Ship bags. A few days before your flight, ship suitcases or holiday gifts to your destination by a documented express service. It’s preferable to losing bags because of re-routed flights and sometimes cheaper than paying airline overweight bag fees.

Know your rights. Airlines are not required to compensate passengers for delayed or cancelled flights, but it never hurts to ask for goodwill vouchers(折扣) for meals, taxis or a room.

1.When making a flight connection, it’s common that you’ll___________.

A. stop in the south B. choose a good city without snowstorm

C. be trapped in the storm D. wait for two or three hours

2.The suggested way for you to rebook your flight is___________.

A. through the phone B. by waiting at the ticket counter

C. by changing another airline D. by surfing the Internet

3.The underlined word “compensate” in the last paragraph can be replaced by “___________”.

A. pay B. ask C. host D. treat

4.What’s the best title of the passage?

A. The Worst Problem in the Trip.

B. The Preparation Before the Flight Trip.

C. How to Book the Plane Ticket.

D. How to Plan the Holiday.

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