题目内容

【题目】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.

1According 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

2The 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

3What 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.

【答案】

1D

2B

3A

【解析】文章介绍了美国《科学》杂志发表的关于西红柿味道的研究,这项研究是由中国农业科学院和美国佛罗里达大学完成的。

1细节理解题。根据第二段内容“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.”(“近年来,消费者经常抱怨现代的西红柿味道远不如以前”“我们的研究为能吃到各种美味的西红柿提供可实现的蓝图。”)可知,此研究背景是现代西红柿味道下降,故选D。

2细节理解题。根据倒数第二段identifying about 250 positions of genes on a chromosome(染色体), which controlled tomato flavor.可知,一些染色体上基因的位置控制西红柿的味道,故B正确。

3推理判断题。根据最后一段内容“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,”可知,此研究为进一步研究改进其他水果作物口味奠定基础,故选A。

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【题目】In the U. S., speaking more than one language fluently is not very common except in Los Angeles, California.

The city has one of the largest population in the U. S. of young people between the ages of 18 and 34. This generation is often called millennials (新千年一代). More than half of millennials in Los Angeles are bilingual (双语的), which means they speak more than one language.

Maria Elena Burgos is cooking a Mexican breakfast. She says making Mexican food is just one of the many traditions in her home. Another is speaking Spanish to her children.

“We want them to be bilingual. We want to keep the Spanish somewhere in their learning too, not only at home.”

When Ms Burgos first came to the United States from Mexico, she learned English. She knew her children would learn English quickly. So she wanted them to speak Spanish at home and study the language at school.

She says being bilingual will give them more opportunities in the future. Knowing Spanish also means the children can talk with their relatives in Mexico.

“When we had our children, one of the decisions we as parents made was to name them with a name that was easily pronounced in English and Spanish.”

Elizabeth wants to know her family’s culture.” “The culture-to go back to our roots because that’s part of who we are.”

Monica wants to pass on the culture to her children.

“It’s nice to know our culture and then to be able to pass it onto our children and grand- children and everyone to let them know where we come from.”

And, Monica says she does not speak only English and Spanish. She has even learned some Korean in school.

1Which of the following is a tradition of Maria?

A. Cooking breakfast for her relatives.

B. Talking with her children in Spanish.

C. Talking with her relatives in Spanish.

D. Forcing her children to speak Spanish.

2What can be inferred from Monica’s words?

A. She doesn’t care where she comes from.

B. She looks forward to learning Spanish.

C. Everyone should know his own culture.

D. She doesn’t like American culture.

3Which of the following is mentioned about children speaking more languages?

A. It can give children more chances in the future.

B. It can make children feel proud before their friends.

C. It can give the children a chance to go to a good college.

D. It can let children go to the places where they want to go.

4What’s the main purpose of this passage?

A. To entertain the readers with a funny story.

B. To inform the readers of a shocking experiment result.

C. To encourage more persons to learn a second language.

D. To tell a truth that many people in Los Angeles are bilingual.

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