We speak of the balance of nature. Biologists talk about biotic pyramids and the web of life. Both are referring to the same phenomenon or existing fact : the many complex ( 复杂的)relationships among organisms and their environment or surroundings.
The pyramid is the biologist’s attempt and try to sketch and describe the energy relationships in nature. You could call it a catalogue or describing record of who eats whom. The land forms the base of the pyramid, and upon it rests a layer or covering or a thickness of plants. Insects such as ants and worms, and herbivores or plant-eating animals, then birds and rodents such as rats and mice, and finally, at the top of the pyramid, the large carnivores or flesh-eating animals, and predatory birds which hunt and eat other animals. Organisms at each level of the pyramid exist by eating those in the layers below, and so are dependent for their survival on the existence of the members of the lower layers.
From the base of the pyramid to the top, populations of organisms decrease. There are always, for example, fewer hawks than gophers, a kind of rats, their prey, and always fewer insects than the plants they eat. But most species of organisms exist on more than one kind of food;each organism forms only one link or ring in a chain of energy transfer or change. These pathways by which energy is cycled through organisms are called food chains. The relationships between organisms form a complex network through which energy from the soil is passed into living things and then, through death and decay or rotting, is returned to the soil. Some energy is always lost in the process or course, and is continually replaced or take the place of by energy from the air and sun through plants, during the process of photosynthesis. But in spite of these gains and losses, the total system does not change much unless interfered with, by man or if man is not in the way. This system is the web of life, a tangle of' food chains, so complicated that we do not yet understand all its workings.
But man's interference has changed many of the relationships. For example, the food chain formed by the soil, bunch-grass, deer, and cougar has been changed to the chain: soil, alfalfa, cow, farmer. Will such changes have serious effects or influence upon the existence of other organisms forming part of the web? If so, what will these effects be, and will they be good or bad? Can we change the web of life without losing something of value in the process? These are some of the questions which the ecologist tries to answer.
Our understanding of the energy relationships in nature is still very limited, but what we have learned so far tells us clearly that when we change the web of life, we run the risk of or we are in danger of losing something which cannot be replaced.
The following story is a true one, and is happening in British Columbia today. It is a dramatic illustration of the energy relationships between organisms, and of the effect man’s intervention has had on the web of life.
1.What is the passage mainly about?
A.Organisms and life.
B.Energy and the balance of nature.
C.A catalogue of who eats whom.
D.Biotic pyramids, webs of life and food chains.
2.The word organisms refers to .
A.life B. energy C. attempt D. relationships
3.A grasshopper is .
A.an insect B. a herbivore C. a rodent D. a carnivore
4.Vegetation is .
A.birds B. animals C. plants D. organisms
5.Look at the picture below. How many food chains can you find in it?
A.2 . B. 4. C. 5. D. 6.
6.The _____is a rodent like a ______.
A.weasel, frog B. grasshopper, rabbit C. frog, rat D. rabbit, mouse
7.If we change the picture of the passage into a pyramid, the _____ is at the top, the ____ at the second layer and the ______ is at the 3rd layer while _____are at the base.
A.hawk, weasel, mouse, plants
B.hawk, grasshopper, rabbit, mice
C.grasshopper , weasel, rabbit , plants
D.hawk, plants, grasshopper, rabbits
8.The population of grasshoppers is always _____ that of frogs.
A.smaller than B. greater than C. the same as D. different from
9.According to the passage, which of the following sayings is true?
A.Food chains are a death and decay process.
B.Photosynthesis is an energy losing process.
C.Each kind of living thing eats only one kind of food.
D.Most kinds of living thing live on more than one kind of organism.
10.What is the passage following this passage most probably about? It is about ______.
A.British Columbia
B.a dramatic illustration
C.man’s influence on the web of life in a certain place
D.the energy relationships between organisms and man’s influence on the web of life
科目:高中英语 来源: 题型:054
完形填空
Life in the 21st century will obviously be very different from ___1___ it is ___2___ now. It is interesting to try to ___3___ what Me will be like ___4___. Our life style will be ___5___ in many ___6___. For example, I think that everyone will live in ___7___. There will be houses under the sea. ___8___ people will get settled ___9___ on the moon and do scientific researches. Every house will have a wireless telephone. Solar energy will be ___10___ used in houses and factories. As for education in the future, I think that children will start ___11___ at the age of 3 .To some extent, computers will take the place of ___12___. People will study ___13___ they are 30. Our __14___ life will be different too. It is possible that people will only work ___15___ hours a day. At the age of ___16___, people will retire and do ___17___ they want. Finally, when we think about the future of travel, it seems to me that it is ___18___ that most people will have a chance to ___19___ in space. Our future is promising, let's work hard for ___20___ our beautiful future.
(1)A.that |
B.which |
C.what |
D.how |
(2)A.seem |
B.to be |
C.like |
D.appear |
(3)A.imagine |
B.make |
C.say |
D.live |
(4)A.on the future |
B.in the future |
C.at the future |
D.for future |
(5)A.the |
B.different |
C.rich |
D.poor |
(6)A.countries |
B.nations |
C.homes |
D.ways |
(7)A.forests |
B.mountains |
C.sea |
D.cities |
(8)A.Some |
B.Most |
C.Every |
D.Very few |
(9)A.up |
B.down |
C.in |
D.with |
(10)A.not |
B.widely |
C.for |
D.easily |
(11)A.to |
B.to work |
C.school |
D.to speak |
(12)A.workers |
B.peasants |
C.scientists |
D.teachers |
(13)A.to |
B.for |
C.until |
D.as |
(14)A.school |
B.working |
C.happy |
D.army |
(15)A.forty |
B.fourteen |
C.four |
D.fourth |
(16)A.seven |
B.seventy |
C.seventeen |
D.forty-five |
(17)A.what |
B.which |
C.whatever |
D.however |
(18)A.impossible |
B.possible |
C.not |
D.freely |
(19)A.do shopping |
B.have medical examination |
C.travel |
D.ride ten-speed bicycle |
(20)A.realizing |
B.imaging |
C.completing |
D.supposing |
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科目:高中英语 来源: 题型:054
完形填空
A Joke on a Friend
Mark twain was a famous American writer.He wrote many famous stories which are still popular in many countries today.Mark Twain was also famous in his day 1 a public speaker.In his speaking Mark Twain always liked 2 funny stories.He also liked to listen to funny stories and to 3 his friends.One day one of his friends 4 his wallet and asked him 5 his train fare for him.
“But I don’t have enough money to pay 6 your fare and my fare,”Mark Twain said.
The friend didn’t know 7 to do.He was very sad. “We can do this.”said Mark Twain.“We can 8 the train and when the conductor comes to take the tickets you can hide 9 my seat.”
Later, 10 ,on the train,when the conductor came to take the tickets,Mark Twain gave him two tickets 11 for Mark Twain and one for his friend.Then 12 a loud voice,Mark Twain explained.
“My friend here is a 13 strange man.When he travels on a train he doesn’t like to sit 14 a seat.He prefers 15 on the floor under the seat.”
Of course,everybody in the train then looked at the poor friend under the seat and laughed at him loudly.
1. | |||
[ ] |
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A.as |
B.f |
C.to |
D.about |
2. | |||
[ ] |
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A.to say |
B.to make |
C.to speak |
D.to tell |
3. | |||
[ ] |
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A.make a joke about | B.have a joke with | ||
C.play jokes on |
D.play a trick on |
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4. | |||
[ ] |
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A.lost |
B.loss |
C.lose |
D.losed |
5. | |||
[ ] |
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A.to buy |
B.to cost |
C.to pay |
D.to charge |
6. | |||
[ ] |
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A.between |
B.both |
C.either |
D.as well as |
7. | |||
[ ] |
|||
A.where |
B.how |
C.which |
D.what |
8. | |||
[ ] |
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A.get on |
B.go on |
C.get in |
D.go in |
9. | |||
[ ] |
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A.behind |
B.under |
C.below |
D.beside |
10. | |||
[ ] |
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A.however |
B.whatever |
C.whenever |
D.wherever |
11. | |||
[ ] |
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A.a |
B.one |
C.a ticket |
D.the one |
12. | |||
[ ] |
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A.at |
B.over |
C.in |
D.on |
13. | |||
[ ] |
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A.more |
B.much |
C.quite |
D.very |
14. | |||
[ ] |
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A.on |
B.onto |
C.at |
D.by |
15. | |||
[ ] |
|||
A.to lay |
B.to lie |
C.to laying |
D.to be lying |
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科目:高中英语 来源: 题型:054
完形填空
“If you haven't got anything interesting 1 , don't say anything 2 .” That's 3 mothers and fathers sometimes 4 their young children.It is not rather a good way 5 the children shut up.However, the Maxism may be worth remembering.
If you are 6 speaking 7 , have you 8 had to stand up in front of a crowd, knees trembling to speak? You have almost certainly been bored by one of those public speakers who can make even 9 seem endless.In our new radio series Speak Out, we examine the art of speaking in English, and take a look at the trick people use to draw and hold the attention of an audience.
The series is based on actual speeches 10 during a public speaking competition organized by the English Speaking Union.Every year the ESU invites pupils from schools all 11 Britain to choose a subject then come to London and give their 12 speeches in front of the audience.
The young speakers-all 13 their mid-teens are judged on their general ability, 14 on their originality and mastery of the subject.We have 15 some of the speeches and you will be able to listen to them in the Speak Out programs.
1. |
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[ ] |
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A.to say |
B.to be said |
C.being said |
D.saying |
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2. |
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[ ] |
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A.at last |
B.at all |
C.in all |
D.at least |
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3. |
||||
[ ] |
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A.what |
B.all |
C.that |
D.which |
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4. |
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[ ] |
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A.have advised |
B.advice |
C.suggest |
D.advise |
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5. |
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[ ] |
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A.of getting |
B.getting |
C.to getting |
D.got |
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6. |
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[ ] |
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A.on a habit of |
B.in the habit of |
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C.out of the habit of |
D.of the habit |
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7. |
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[ ] |
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A.in the public |
B.in public |
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C.at public |
D.before the public |
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8. |
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[ ] |
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A.ever |
B.yet |
C.still |
D.even |
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9. |
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[ ] |
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A.three-minutes speech |
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B.a three-minute speech |
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C.a three-minutes speech |
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D.three minutes speech |
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10. |
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[ ] |
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A.are made |
B.being made |
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C.having been made |
D.made |
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11. |
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[ ] |
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A.about |
B.around |
C.over |
D. |
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12. |
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[ ] |
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A.prepared |
B.preparing |
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C.having prepared |
D.being prepared |
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13. |
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[ ] |
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A.on |
B.at |
C.of |
D.in |
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14. |
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[ ] |
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A.as good as |
B.as well as |
C.as many |
D.as well |
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15. |
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[ ] |
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A.written |
B.read |
C.recorded |
D.recognized |
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科目:高中英语 来源: 题型:054
完形填空
When I was 16 years old, I made my first visit to the United States. It wasn't the first time I had been __1__. Like most English children I learned French __2__ school and I had often been to France, so I __3__ speaking a foreign language to people who didn't understand __4__. But when I went to America I was really looking forward to __5__ a nice easy holiday without any __6__ problems.
__7__ wrong I was! The misunderstanding began at the airport. I was looking for a __8__ telephone to give my American friend Danny a __9__and tell her that I had arrived. A friendly old man saw me looking lost and asked __10__ he could help me. “Yes”, I said, “I want to give my friend a ring. ” “Well, that's __11__, ” he exclaimed. “Are you getting __12__? But aren't you a bit __13__?”“Who is talking about marriage?”I replied. “I __14__ want to give my friend a ring to tell her I've arrived. Can you tell me __15__ there's a phone box?”“Oh!”he said, “there's a phone downstairs.”
When at last we__16__ meet up, Danny explained the misunderstandings to me.“Don't worry, ” she said to me. “I had so many __17__ at first. There are lots of words which the Americans __18__ differently in meaning from us British. You'll soon get used to __19__ funny things they say. Most of the __20__ British and American people understand each other!”
(1)A.out |
B.away |
C.outside |
D.abroad |
(2)A.from |
B.during |
C.at |
D.after |
(3)A.get used to |
B.was used to |
C.used to |
D.used |
(4)A.English |
B.French |
C.Russian |
D.Latin |
(5)A.buying |
B.having |
C.giving |
D.receiving |
(6)A.time |
B.human |
C.language |
D.money |
(7)A.Too |
B.What a |
C.What |
D.How |
(8)A.cheap |
B.popular |
C.public |
D.good |
(9)A.letter |
B.ring |
C.news |
D.information |
(10)A.that |
B.if |
C.where |
D.when |
(11)A.well |
B.over |
C.nice |
D.ring |
(12)A.up |
B.lost |
C.down |
D.married |
(13)A.small |
B.little |
C.old |
D.young |
(14)A.very |
B.just |
C.just now |
D.so |
(15)A.where |
B.in which |
C.over there |
D.that |
(16)A.did |
B.do |
C.could |
D.had |
(17)A.trouble |
B.difficulties |
C.things |
D.fun |
(18)A.write |
B.speak |
C.use |
D.read |
(19)A.every |
B.these |
C.some |
D.all the |
(20)A.chance |
B.situation |
C.condition |
D.time |
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科目:高中英语 来源:英语教研室 题型:054
完形填空
One summer night, on nay way home from work I decided to see a movie. I knew the theatre would be air-conditioned and I couldn't face my 1 apartment.
Sitting in the theatre I had to look through the 2 between the two tall heads in front of me. I had to keep 3 the angle(角度)every time she leaned over to talk to him, 4 he leaned over to kiss her. Why do Americans show such 5 in a public place?
I thought the movie would be good for my English, but it 6 that it was an Italian movie. 7 about half an hour I decided to give up the movie and 8 my attention on my popcorn(爆玉米花). I've never understood why they give you so much popcorn! It tasted pretty good, 9 . After a while I heard 10 more of the romantic-sounding Italians. I just heard the 11 of the popcorn crunching(咀嚼)between my teeth. My thought started to 12 . I remembered that when I was in South Korea, I 13 to watch Kojak on TV frequently. He spoke perfect Korean-I was really amazed. He seemed like a good friend to me 14 I saw him again in New York speaking 15 English instead of perfect Korean. He didn't even have a Korean accent and I 16 as if I had been betrayed(背叛).
When our family moved to the United States six years ago, none of us spoke any English. 17 we had begun to learn a few words, my mother suggested that we all should speak English at home. Everyone agreed, but our house became very 18 and we all seemed to avoid each other. We sat at the dinner table in silence, preferring that to 19 in a difficult language. Mother tried to say something in English but it 20 out all wrong and we all burst into laughter and decided to forget it! We've been speaking Korean at home ever since.
(1)A.warm |
B.hot |
C.heated |
D.cool |
(2)A.room |
B.blank |
C.break |
D.opening |
(3)A.trying |
B.making |
C.replacing |
D.changing |
(4)A.while |
B.whenever |
C.or |
D.and |
(5)A.attraction |
B.attention |
C.affection |
D.thought |
(6)A.came to |
B.came up |
C.turned up |
D.turned out |
(7)A.Within |
B.After |
C.For |
D.Over |
(8)A.fix |
B.lay |
C.put |
D.leave |
(9)A.too |
B.yet |
C.though |
D.still |
(10)A.much |
B.any |
C.no |
D.few |
(11)A.voice |
B.sound |
C.noise |
D.tone |
(12)A.wonder |
B.wander |
C.imagine |
D.change |
(13)A.enjoyed |
B.happened |
C.turned |
D.used |
(14)A.until |
B.because |
C.then |
D.therefore |
(15)A.false |
B.informal |
C.perfect |
D.practical |
(16)A.felt |
B.looked |
C.seemed |
D.appeared |
(17)A.Since |
B.If |
C.Before |
D.Once |
(18)A.empty |
B.quiet |
C.cold |
D.calm |
(19)A.telling |
B.whispering |
C.saying |
D.talking |
(20)A.worked |
B.got |
C.came |
D.made |
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