When an ant dies, other ants move the dead insect out. Sometimes, the dead ant get moved away very soon—within an hour of dying. This behavior is interesting to scientists, who wonder how ants know for sure—and so soon—that another ant is dead.
One scientist recently came up with a way to explain this ant behavior. Dong-Hwan Choe is a biologist. Choe found that Argentine ants have a chemical on the outside of their bodies that signals to other ants, “I’m dead—take me away.”
But there’s a twist to Choe’s discovery. Choe says that the living ants—not just the dead ones —have this death chemical. In other words, while an ant crawls around, perhaps in a picnic or home, it’s telling other ants that it’s dead.
What keeps ants from dragging away the living ants? Choe found that Argentine ants have two additional chemicals on their bodies, and these tell nearby ants something like, “Wait—I’m not dead yet.” So Choe’s research turned up two sets of chemical signals in ants: one says, “I’m dead,” and the other set says, “I’m not dead yet.”
Other scientists have tried to figure out how ants know when another ant is dead. If an ant is knocked unconscious, for example, other ants leave it alone until it wakes up. That means ants know that unmoving ants can still be alive.
Choe suspects that when an Argentine ant dies, the chemical that says “Wait- I’m not dead yet” quickly goes away. Once that chemical is gone, only the one that says “I’m dead” is left. “It’s because the dead ant no longer smells like a living ant that it gets carried to the graveyard, not because its body releases new unique chemicals after death,” said Choe. When other ants detect the “dead” chemical without the “not dead yet” chemical, they drag away the body.
Understanding this behavior may help scientists figure out how to stop Argentine ants from invading new places and causing problems. Choe would like to find a way to use the newly discovered chemicals to spread ant killer to Argentine ant nests.
The ants’ removal behavior is important to the overall health of the nest. “Being able to quickly remove dead individuals and other possible sources of disease is extremely important to all animals living in societies, including us,” says Choe. “Think about all the effort and money that we invest daily in waste management.”
51. The underlined word “twist” in Paragraph 3 means _____.
A. an unexpected change B. a clear mistake
C. an important key D. a shocking conclusion
52. Ants judge whether another one is dead or not depending on ______.
A. the sense of taste B. the sense of smell
C. the sense of touch D. the sense of sight
53. The result of the research can be used to ______.
A. kill troublesome pests
B. solve the problem of endangered species
C. prevent further expansion of the ants’ territory
D. keep the balance of nature
54. Why is it important to remove dead individuals?
A. Because it is easier to manage the living.
B. Because it can save money to deal with the waste.
C. Because it can provide more space for the living.
D. Because it can keep the living from suffering disease.
55. What might be the best title of the text?
A. Dead or living? It is easy to judge
B. Pulling away the dead ants is a difficult task
C. Ant nests have great undertaking capacity
D. Leaving it alone or taking it away? Ants feel puzzled
科目:高中英语 来源: 题型:阅读理解
Once in a blue moon there is one on New Year's Eve. Revelers ringing in 2010 will be treated to a so-called blue moon. According to popular definition, a blue moon is the second full moon in a month. But don't 1 it to be blue - the name has nothing to 2 the color of our closest celestial(天体) neighbor.
A full moon 3 on December 2. It will appear again on Thursday in time for the New Year's countdown.
"If you're in Times Square, you'll see the 4 moon right above you. It's going to be that brilliant," said Jack Horkheimer, director emeritus of the Miami Space Transit Planetarium and host of a weekly astronomy TV show.
The New Year's Eve blue moon will be 5 in the United States, Canada, Europe, South America and Africa. For partygoers in Australia and Asia, the full moon does not show up 6 New Year's Day, making January a blue moon month for them.
However, the Eastern Hemisphere can celebrate with a partial lunar eclipse(月蚀) on New Year's Eve when 7 of the moon enters the Earth's shadow. The 8 will not be visible in the Americas.
A full moon occurs 9 29.5 days, and most years have 12. 10 , an extra full moon in a month - a blue moon - occurs every 2.5 years. The 11 time there was a lunar double take was in May 2007. New Year's Eve blue moons are rarer, occurring every 19 years. The last time was in 1990; the next one won't 12 again until 2028.
Blue moons have no astronomical 13 , said Greg Laughlin, an astronomer at the University of California, Santa Cruz.
"`Blue moon' is just a 14 in the same sense as a `hunter's moon' or a `harvest moon,'" Laughlin said in an e-mail.
The popular definition of blue moon 15 after a writer for Sky & Telescope magazine in 1946 misunderstood the Maine Farmer's Calendar and marked a blue moon as the second full moon in a month. In fact, the calendar 16 a blue moon as the third full moon in a season with four full moons, not the usual three.
Though Sky & Telescope corrected the 17 decades later, the definition caught on. For purists(语言纯正癖者), however, this New Year's Eve full moon doesn't even qualify as a 18 moon. It's just the first full moon of the winter season.
In a tongue-in-cheek essay 19 on the magazine's Web site this week, senior contributing editor Kelly Beatty wrote: "If skies are clear when I'm 20 celebrating, I'll take a peek(眯着眼睛看) at that brilliant orb(天体) as it rises over the Boston skyline to see if it's an icy shade of blue. Or maybe I'll just howl."
( ) 1. A. wish B. wait C. hope D. expect
( ) 2. A. deal with B. do with C. develop with D. form into
( ) 3. A. occurred B. came C. ran D. went
( ) 4. A. full B. half C. bright D. part
( ) 5. A. out of sight B. visible C. big D. clear
( ) 6. A. until B. when C. before D. since
( ) 7. A. part B. all C. any D. none
( ) 8. A. moon B. eclipse C. sun D. shadow
( ) 9. A. each B. every C. either D. all
( ) 10. A. On the whole B. Generally speaking C. On average D. In addition
( ) 11. A. last B. next C. other D. another
( ) 12. A. go B. see C. come D. look
( ) 13. A. point B. evident C. theory D. significance
( ) 14. A. name B. object C. phenomenon D. tradition
( ) 15. A. created B. came about C. made D. copied
( ) 16. A. named B. called C. introduced D. defined
( ) 17. A. error B. name C. reality D. number
( ) 18. A. blue B. red C. yellow D. grey
( ) 19. A. published B. posted C. printed D. written
( ) 20. A. in B. out C. away D. on
查看答案和解析>>
科目:高中英语 来源: 题型:阅读理解
Once in a blue moon there is one on New Year's Eve. Revelers ringing in 2010 will be treated to a so-called blue moon. According to popular definition, a blue moon is the second full moon in a month. But don't 1 it to be blue - the name has nothing to 2 the color of our closest celestial(天体) neighbor.
A full moon 3 on December 2. It will appear again on Thursday in time for the New Year's countdown.
"If you're in Times Square, you'll see the 4 moon right above you. It's going to be that brilliant," said Jack Horkheimer, director emeritus of the Miami Space Transit Planetarium and host of a weekly astronomy TV show.
The New Year's Eve blue moon will be 5 in the United States, Canada, Europe, South America and Africa. For partygoers in Australia and Asia, the full moon does not show up 6 New Year's Day, making January a blue moon month for them.
However, the Eastern Hemisphere can celebrate with a partial lunar eclipse(月蚀) on New Year's Eve when 7 of the moon enters the Earth's shadow. The 8 will not be visible in the Americas.
A full moon occurs 9 29.5 days, and most years have 12. 10 , an extra full moon in a month - a blue moon - occurs every 2.5 years. The 11 time there was a lunar double take was in May 2007. New Year's Eve blue moons are rarer, occurring every 19 years. The last time was in 1990; the next one won't 12 again until 2028.
Blue moons have no astronomical 13 , said Greg Laughlin, an astronomer at the University of California, Santa Cruz.
"`Blue moon' is just a 14 in the same sense as a `hunter's moon' or a `harvest moon,'" Laughlin said in an e-mail.
The popular definition of blue moon 15 after a writer for Sky & Telescope magazine in 1946 misunderstood the Maine Farmer's Calendar and marked a blue moon as the second full moon in a month. In fact, the calendar 16 a blue moon as the third full moon in a season with four full moons, not the usual three.
Though Sky & Telescope corrected the 17 decades later, the definition caught on. For purists(语言纯正癖者), however, this New Year's Eve full moon doesn't even qualify as a 18 moon. It's just the first full moon of the winter season.
In a tongue-in-cheek essay 19 on the magazine's Web site this week, senior contributing editor Kelly Beatty wrote: "If skies are clear when I'm 20 celebrating, I'll take a peek(眯着眼睛看) at that brilliant orb(天体) as it rises over the Boston skyline to see if it's an icy shade of blue. Or maybe I'll just howl."
( ) 1. A. wish B. wait C. hope D. expect
( ) 2. A. deal with B. do with C. develop with D. form into
( ) 3. A. occurred B. came C. ran D. went
( ) 4. A. full B. half C. bright D. part
( ) 5. A. out of sight B. visible C. big D. clear
( ) 6. A. until B. when C. before D. since
( ) 7. A. part B. all C. any D. none
( ) 8. A. moon B. eclipse C. sun D. shadow
( ) 9. A. each B. every C. either D. all
( ) 10. A. On the whole B. Generally speaking C. On average D. In addition
( ) 11. A. last B. next C. other D. another
( ) 12. A. go B. see C. come D. look
( ) 13. A. point B. evident C. theory D. significance
( ) 14. A. name B. object C. phenomenon D. tradition
( ) 15. A. created B. came about C. made D. copied
( ) 16. A. named B. called C. introduced D. defined
( ) 17. A. error B. name C. reality D. number
( ) 18. A. blue B. red C. yellow D. grey
( ) 19. A. published B. posted C. printed D. written
( ) 20. A. in B. out C. away D. on
查看答案和解析>>
科目:高中英语 来源: 题型:阅读理解
There are some very good things about open education.This way of teaching allows the students to grow as people, and to develop their own interests in many subjects.Open education allows students to be responsible for their own education, as they are responsible for what they do in life.Some students do badly in traditional classrooms.The open classroom may allow them to enjoy learning. Some students will be happier in an open education school. They will not have to worry about grades or rules.For students who worry about these things a lot, it is a good idea to be in an open classroom.
But many students will not do well in an open classroom.For some students, there are too few rules.These students will do little in school. They will not make good use of open education.Because open education is so different from traditional education, these students may have a problem of getting used to making so many choices.For many students it is important to have some rules in the classroom.They worry about the rules even when there are no rules.Even a few rules will help this kind of students.The last point about open education is that some traditional teachers do not like it. Many teachers do not believe in open education.Teachers who want to have an open classroom may have many problems at their school.
You now know what open education is.Some of its good points and bad points have been explained.You may have your own opinion about open education.The writer thinks that open education is a good idea, but only in theory.In actual fact, it may not work very well in a real class or school. The writer believes that most students, but of course not all students want some structure in their classes.They want and need to have rules.In some cases, they must be made to study some subjects.Many students are pleased to find subjects they have to study interesting.They would not study those subjects if they did not have to.
According to the passage, which of the following is NOT the reason why some students like open education?
A. The open classroom may allow them to enjoy learning.
B. Open education allows students to be responsible for their own future.
C. Open education allows the students to develop their own interests.
D. Open education has fewer rules.
From the passage we can learn that___________.
A. the writer believes that all students don’t want some structure in their classes
B. the writer believes that all students want some structure in their classes
C. nearly all teachers like open education
D. only the students that worry about rules or grades a lot like to be in an open classroom
Some students will do little in an open classroom because _______.
A. there are too few rules
B. they hate activities
C. open education is similar to traditional education
D. they worry about the rules
Which is NOT mentioned according to the passage given?
A. some advantages about open education
B. some disadvantages about open education
C. some students’ feelings in an open education school
D. the writer’s opinion about open education is the same as all the students’
Which of the following can best summarize the passage?
A. Many students like open education.
B. Open education is better than traditional education.
C. Open education is a really complicated idea.
D. Open education is a good idea in practice.
查看答案和解析>>
科目:高中英语 来源: 题型:阅读理解
Once in a blue moon there is one on New Year's Eve. Revelers ringing in 2010 will be treated to a so-called blue moon. According to popular definition, a blue moon is the second full moon in a month. But don't 1 it to be blue - the name has nothing to 2 the color of our closest celestial(天体) neighbor.
A full moon 3 on December 2. It will appear again on Thursday in time for the New Year's countdown.
"If you're in Times Square, you'll see the 4 moon right above you. It's going to be that brilliant," said Jack Horkheimer, director emeritus of the Miami Space Transit Planetarium and host of a weekly astronomy TV show.
The New Year's Eve blue moon will be 5 in the United States, Canada, Europe, South America and Africa. For partygoers in Australia and Asia, the full moon does not show up 6 New Year's Day, making January a blue moon month for them.
However, the Eastern Hemisphere can celebrate with a partial lunar eclipse(月蚀) on New Year's Eve when 7 of the moon enters the Earth's shadow. The 8 will not be visible in the Americas.
A full moon occurs 9 29.5 days, and most years have 12. 10 , an extra full moon in a month - a blue moon - occurs every 2.5 years. The 11 time there was a lunar double take was in May 2007. New Year's Eve blue moons are rarer, occurring every 19 years. The last time was in 1990; the next one won't 12 again until 2028.
Blue moons have no astronomical 13 , said Greg Laughlin, an astronomer at the University of California, Santa Cruz.
"`Blue moon' is just a 14 in the same sense as a `hunter's moon' or a `harvest moon,'" Laughlin said in an e-mail.
The popular definition of blue moon 15 after a writer for Sky & Telescope magazine in 1946 misunderstood the Maine Farmer's Calendar and marked a blue moon as the second full moon in a month. In fact, the calendar 16 a blue moon as the third full moon in a season with four full moons, not the usual three.
Though Sky & Telescope corrected the 17 decades later, the definition caught on. For purists(语言纯正癖者), however, this New Year's Eve full moon doesn't even qualify as a 18 moon. It's just the first full moon of the winter season.
In a tongue-in-cheek essay 19 on the magazine's Web site this week, senior contributing editor Kelly Beatty wrote: "If skies are clear when I'm 20 celebrating, I'll take a peek(眯着眼睛看) at that brilliant orb(天体) as it rises over the Boston skyline to see if it's an icy shade of blue. Or maybe I'll just howl."
( ) 1. A. wish B. wait C. hope D. expect
( ) 2. A. deal with B. do with C. develop with D. form into
( ) 3. A. occurred B. came C. ran D. went
( ) 4. A. full B. half C. bright D. part
( ) 5. A. out of sight B. visible C. big D. clear
( ) 6. A. until B. when C. before D. since
( ) 7. A. part B. all C. any D. none
( ) 8. A. moon B. eclipse C. sun D. shadow
( ) 9. A. each B. every C. either D. all
( ) 10. A. On the whole B. Generally speaking C. On average D. In addition
( ) 11. A. last B. next C. other D. another
( ) 12. A. go B. see C. come D. look
( ) 13. A. point B. evident C. theory D. significance
( ) 14. A. name B. object C. phenomenon D. tradition
( ) 15. A. created B. came about C. made D. copied
( ) 16. A. named B. called C. introduced D. defined
( ) 17. A. error B. name C. reality D. number
( ) 18. A. blue B. red C. yellow D. grey
( ) 19. A. published B. posted C. printed D. written
( ) 20. A. in B. out C. away D. on
查看答案和解析>>
科目:高中英语 来源:四川省自贡市普高2010级第四次诊断性考试(英语) 题型:阅读理解
As a parent you have the responsibility to help your children understand money. But first you will need to understand your own attitude towards money, and make sure to practise what you teach.
Ask yourself what things that cost money are the most important to you. Also ask yourself what financial goals do you have for yourself and your family this year, in five years, and so on?
Take a minute to write down a list. Below are some ideas to get you started. There’s no right or wrong here. This exercise is just to help you grasp what money means to you so that you can help your children understand your values.
◆ Home
◆ Household expenses
◆ Education
◆ Recreation, entertainment
◆ Savings
◆ Charitable contributions
You can start discussing money when your children are as young as three years old. The best time to teach a child anything is when he or she shows an interest. So he prepared to start talking about money when your child starts asking you to buy candy or toys.
Begin by showing how money is exchanged for items or services. Show your children how money works by allowing them to buy something, such as a toy or a book.
Be open and honest, and explain to your children why they can or cannot have certain items. If you must say no to a child’s request to spend money, you might say, “You have enough toy trucks now.” Or, if the request is for multiple items, “You have a choice to make, between this toy and that one.”
You can start explaining the bigger picture once your children understand the basic function of money. Show an older child how money is used to provide for the whole family.
45. Why should parents understand their own money attitudes first?
A. To help their children earn money. B. To set an exampel to their children.
C. To help them set financial goals. D. To help them tell right from wrong.
46. Which of the following is NOT one of the major categories of things that cost money listed in the article?
A. Travel and investments. B. Household expenses.
C. Education and entertainment. D. Savings and charitable contributions.
47. Which of the following is NOT a way to teach the children about money?
A. Showing how money is exchanged.
B. Allowing children to buy whatever they like.
C. Explaining the limits involved in using money.
D. Having an open discussion about money.
48. According to the passage, when should parents start teaching a child about money?
A. When the child can understand its basic function.
B. When the child can understand how money is used to provide for the whole family.
C. When the child knows how to support a family.
D. As young as three, or when they start showing an interest.
查看答案和解析>>
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com