共用题干 A Biological ClockEvery living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective coco

请阅读Passage 1，完成题：
Modern scientists divide the process of dying into two stages--clinical or temporary death and biological death. Clinical death occurs when the vital organs, such as the heart or lungs, have ceased to function, but have not suffered permanent damage. The organism can still be revived.
Biological death occurs when changes in the organism lead to the disintegration of vital cells and tissues. Death is then irreversible and final.
Scientists have been seeking a way to prolong the period of clinical death so that the organism can be revived before biological death occurs. The best method developed so far involves cooling of the organism, combined with narcotic sleep. By slowing down the body's metabolism, cooling delays the processes leading to biological death.
To illustrate how this works, scientists performed an experiment on a six-year-old female monkey called Keta. The scientists put Keta to sleep with a narcotic. Then they surrounded her body with ice-bags and began checking her body temperature. When it had dropped to 28 degrees the scientists began draining blood from its body. The monkey's blood pressure decreased and an hour later both the heart and breathing stopped; clinical death set in. For twenty minutes Keta remained in this state. Her temperature dropped to 22 degrees. At this point the scientists pumped blood into its body in the direction of the heart and started artificial breathing. After two minutes the monkey's heart became active once more. After fifteen minutes, spontaneous breathing began,and after four hours Keta opened her eyes and lifted her head. After six hours, when the scientists tried to give her a penicillin injection, Keta seized the syringe and ran with it around the room. Her behavior differed little from that of a healthy animal.

The best statement of the main idea of this passage is that__________.
查看材料

A．scientists have found a way to prolong the period of clinical death
B．biological death occurs when vital organs have suffered permanent damage
C．modern scientists divide the process of dying into clinical and biological death
D．cooling delays the processes leading to biological death

Modern scientists divide the process of dying into two stages--clinical or temporary death and biological death. Clinical death occurs when the vital organs, such as the heart or lungs, have ceased to function, but have not suffered permanent damage. The organism can still be revived. Biological death occurs when changes in the organism lead to the disintegration of vital cells and tissues. Death is then irreversible and final.
Scientists have been seeking a way to prolong the period of clinical death so that the organism can be revived before biological death occurs. The best method developed so far involves cooling of the organism, combined with narcotic sleep. By slowing down the body's metabolism, cooling delays the processes leading to biological death.
To illustrate how this works, scientists performed an experiment on a six-year-old female monkey called Keta. The scientists put Keta to sleep with a narcotic. Then they surrounded her body with ice-bags and began checking her body temperature. When it had dropped to 28 degrees the scientists began draining blood from its body. The monkey's blood pressure decreased and an hour later both the heart and breathing stopped; clinical death set in. For twenty minutes Keta remained in this state. Her temperature dropped to 22 degrees. At this point the scientists pumped blood into its body in the direction of the heart and started artificial breathing. After two minutes the monkey's heart became active once more. After fifteen minutes, spontaneous breathing began, and after four hours Keta opened her eyes and lifted her head. After six hours, when the scientists tried to give her a penicillin injection, Keta seized the syringe and ran with it around the room. Her behavior differed little from that of a healthy animal.
The best statement of the main idea of this passage is that _____

A.scientists have found a way to prolong the period of clinical death
B.biological death occurs when vital organs have suffered perumnent damage
C.modern scientists divide the process of dying into clinical and biological death
D.cooling delays the processes leading to biological death

The best statement of the main idea of this passage is that__________.

A.scientists have found a way to prolong the period of clinical death
B.biological death occurs when vital organs have suffered permanent damage
C.modern scientists divide the process of dying into clinical and biological death
D.cooling delays the processes leading to biological death

共用题干
A Biological Clock
Every living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective cocoons and fly away,and it tells animals and human beings when to eat,sleep and wake.
Events outside the plant and anima______(53)the actions of some biological clocks.Sci- entists recently found,for example,that a tiny animal changes the color of its fur______(54) the number of hours of daylight.In the short______(55)of winter,its fur becomes white.The fur becomes gray brown in color in the longer hours of daylight in summer.
Inner signals control other biological clocks.German scientists found that some kind of internal clock seems to order birds to begin their long migration______(56)twice each year. Birds ______(57)flying become restless when it is time for the trip,______(58)they become calm again when the time of the flight has ended.
Scientists say they are beginning to learn which______(59)of the brain contain biologica] clocks.An American researcher,Martin Moorhead,said a small group of cells near the front of the brain______（60)to control the timing of some of our actions.These______(61)tell a person when to______(62),when to sleep and when to seek food.Scientists say there proba- bly are other biological clock cells that control other body activities.
Dr Moorhead is studying______(63)our biological clocks affect the way we do our work .For example,most of us have great difficulty if we must often change to different work hours.
______(64)can take many days for a human body to accept the major change in work hours .Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers.He said______(65)understanding could cut sickness and accidents at work and would help increase a factory's production.

65._________
A: if
B:such
C: with
D: so

共用题干
A Biological Clock
Every living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective cocoons and fly away,and it tells animals and human beings when to eat,sleep and wake.
Events outside the plant and anima______(53)the actions of some biological clocks.Sci- entists recently found,for example,that a tiny animal changes the color of its fur______(54) the number of hours of daylight.In the short______(55)of winter,its fur becomes white.The fur becomes gray brown in color in the longer hours of daylight in summer.
Inner signals control other biological clocks.German scientists found that some kind of internal clock seems to order birds to begin their long migration______(56)twice each year. Birds ______(57)flying become restless when it is time for the trip,______(58)they become calm again when the time of the flight has ended.
Scientists say they are beginning to learn which______(59)of the brain contain biologica] clocks.An American researcher,Martin Moorhead,said a small group of cells near the front of the brain______（60)to control the timing of some of our actions.These______(61)tell a person when to______(62),when to sleep and when to seek food.Scientists say there proba- bly are other biological clock cells that control other body activities.
Dr Moorhead is studying______(63)our biological clocks affect the way we do our work .For example,most of us have great difficulty if we must often change to different work hours.
______(64)can take many days for a human body to accept the major change in work hours .Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers.He said______(65)understanding could cut sickness and accidents at work and would help increase a factory's production.

51._________
A: animals
B: plants
C:humans
D: scientists

It was about 100 years ago____this beautiful clock was made

A.Neither
B.since
C.then
D.when

共用题干
Keeping Cut Flowers（鲜切花）
1. While everybody enjoys fresh cut flowers around his/her house,few people know how to keep them for as long as possible .This may be done by keeping in mind a few simple facts.
2. An important thing to remember about cut flowers is that they are sensitive to temperature.For example,studies have shown that cut carnations（康乃馨）retain their freshness eight times lon-ger when kept at 12℃than when kept at 26℃．Keeping freshly harvested flowers at the right tem-peratures is probably the most important aspect of flower care.
3. Flowers are not intended by nature to live very long.Their biological purpose is simply to at-tract birds or insects,such as bees,for pollination（授粉）.After that,they quickly dry up and die. The process by which flowers consume oxygen and produce carbon dioxide（二氧化碳）, called respiration（呼吸）,generates the energy the flower needs to give the flower its shape and color. The making of seeds also depends on this energy.While all living things respire,flowers have a high level of respiration.A result of all this respiration is heat,and for flowers the level of heat relative to the mass of the flower is very high.Respiration also brings about the eventual death of the flower. Thus the greater the level of respiration,the sooner the flower dies.
4. How,then,to control the rate at which flowers die?By controlling respiration.How is respi-ration controlled?By controlling temperature .We know that respiration produces heat,but the re-verse（相反的过程）is also true. Thus by maintaining low temperatures , respiration is reduced and the cut flower will age more slowly.
5. Another vital factor in keeping cut flowers is the quality of the water in which they are placed. Flowers find it difficult to“drink”water that is dirty or otherwise polluted.Even when water looks and smells clean,it almost certainly contains harmful substances that can endanger the flowers. To rid the water of these unwanted substances, household chlorine bleach（漂白剂）can be used in small quantities.It is recommended that 15 drops of chlorine bleach(at 4%solution)be add-ed to each litre of water. The water and solution should also be replaced each day.

Paragraph 2________
A: Control of Respiration
B: Beauty of Fresh Cut Flowers
C: Role of Respiration
D: Most Important Aspect of Flower Care
E: Need for Cleanwater
F:.Ways of Stopping Respiration

Decide on the correct stress pattern of the answer to the question: When shall we go to school?

A.I think we should leave at seven o'clock.
B.I think we should leave at seven o'clock.
C.I think we should leave at seven o'clock.
D.I think we should leave at seven o'clock.

请阅读Passage 1，完成题：
Modern scientists divide the process of dying into two stages--clinical or temporary death and biological death. Clinical death occurs when the vital organs, such as the heart or lungs, have ceased to function, but have not suffered permanent damage. The organism can still be revived.
Biological death occurs when changes in the organism lead to the disintegration of vital cells and tissues. Death is then irreversible and final.
Scientists have been seeking a way to prolong the period of clinical death so that the organism can be revived before biological death occurs. The best method developed so far involves cooling of the organism, combined with narcotic sleep. By slowing down the body's metabolism, cooling delays the processes leading to biological death.
To illustrate how this works, scientists performed an experiment on a six-year-old female monkey called Keta. The scientists put Keta to sleep with a narcotic. Then they surrounded her body with ice-bags and began checking her body temperature. When it had dropped to 28 degrees the scientists began draining blood from its body. The monkey's blood pressure decreased and an hour later both the heart and breathing stopped; clinical death set in. For twenty minutes Keta remained in this state. Her temperature dropped to 22 degrees. At this point the scientists pumped blood into its body in the direction of the heart and started artificial breathing. After two minutes the monkey's heart became active once more. After fifteen minutes, spontaneous breathing began,and after four hours Keta opened her eyes and lifted her head. After six hours, when the scientists tried to give her a penicillin injection, Keta seized the syringe and ran with it around the room. Her behavior differed little from that of a healthy animal.

This passage focuses on__________.
查看材料

A．the difference between biological and clinical death
B．the process of dying
C．prolonging the period of clinical death
D．the nature of clinical death

The first paragraph tells us that the author__________.

A.lost his heating when he was a child
B.didn't like his brothers and sisters
C.was born to a naturalist's family
D.was interested in flowers and insects in his childhood

共用题干
The Death

Modern scientists divide the process of dying into two stages一(46)________.Clinical death occurs when the vital organs,such as the heart or lungs,have ceased to function,but have not suffered permanent damage. The organism can still be revived（复活）.Biological death occurs when changes in the organism lead to the disintegration（解体）of vital cells and tissues. Death is then irreversible and final.
Scientists have been seeking a way to prolong the period of clinical death so that(47) ________.The best method developed so far involves cooling of the organism,combined with narcotic（麻醉的）sleep. By slowing down the body's metabolism（新陈代谢）,cooling delays the processes leading to biological death.
To illustrate how this works,scientists performed an experiment on a six-year-old female monkey called Keta.(48)_________.Then they surrounded her body with ice-bags and began checking her body temperature.When it had dropped to 28 degrees the scientists began draining blood from its body.The monkey's blood pressure decreased and an hour later both the heart and breathing stopped,clinical death set in.For twenty minutes Keta remained in this state.Her temperature dropped to 22 degrees.At this point the scientists pumped blood into its body in the direction of the heart and started artificial breathing.(49)_______.After fifteen minutes,spontaneous breathing began,and after four hours Keta opened her eyes and lifted her head.After six hours,when the scientists tried to give her a penicillin injection,Keta seized the syringe and ran with it around the room.(50)__________.

________（50）
A:the organism can be revived before biological death occurs
B:clinical or temporary death and biological death
C:After two minutes the monkey's heart became active once more
D:Her behavior differed little from that of a healthy animal
E:The scientists put Keta to sleep with a narcotic
F:Clinical death process should be prolonged

共用题干
A Biological Clock
Every living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective cocoons and fly away,and it tells animals and human beings when to eat,sleep and wake.
Events outside the plant and anima______(53)the actions of some biological clocks.Sci- entists recently found,for example,that a tiny animal changes the color of its fur______(54) the number of hours of daylight.In the short______(55)of winter,its fur becomes white.The fur becomes gray brown in color in the longer hours of daylight in summer.
Inner signals control other biological clocks.German scientists found that some kind of internal clock seems to order birds to begin their long migration______(56)twice each year. Birds ______(57)flying become restless when it is time for the trip,______(58)they become calm again when the time of the flight has ended.
Scientists say they are beginning to learn which______(59)of the brain contain biologica] clocks.An American researcher,Martin Moorhead,said a small group of cells near the front of the brain______（60)to control the timing of some of our actions.These______(61)tell a person when to______(62),when to sleep and when to seek food.Scientists say there proba- bly are other biological clock cells that control other body activities.
Dr Moorhead is studying______(63)our biological clocks affect the way we do our work .For example,most of us have great difficulty if we must often change to different work hours.
______(64)can take many days for a human body to accept the major change in work hours .Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers.He said______(65)understanding could cut sickness and accidents at work and would help increase a factory's production.

52._________
A: insects
B: birds
C: fish
D: snakes

共用题干
A Biological Clock
Every living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective cocoons and fly away,and it tells animals and human beings when to eat,sleep and wake.
Events outside the plant and anima______(53)the actions of some biological clocks.Sci- entists recently found,for example,that a tiny animal changes the color of its fur______(54) the number of hours of daylight.In the short______(55)of winter,its fur becomes white.The fur becomes gray brown in color in the longer hours of daylight in summer.
Inner signals control other biological clocks.German scientists found that some kind of internal clock seems to order birds to begin their long migration______(56)twice each year. Birds ______(57)flying become restless when it is time for the trip,______(58)they become calm again when the time of the flight has ended.
Scientists say they are beginning to learn which______(59)of the brain contain biologica] clocks.An American researcher,Martin Moorhead,said a small group of cells near the front of the brain______（60)to control the timing of some of our actions.These______(61)tell a person when to______(62),when to sleep and when to seek food.Scientists say there proba- bly are other biological clock cells that control other body activities.
Dr Moorhead is studying______(63)our biological clocks affect the way we do our work .For example,most of us have great difficulty if we must often change to different work hours.
______(64)can take many days for a human body to accept the major change in work hours .Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers.He said______(65)understanding could cut sickness and accidents at work and would help increase a factory's production.

63._________
A: how
B: why
C: where
D: what

共用题干
Keeping Cut Flowers（鲜切花）
1. While everybody enjoys fresh cut flowers around his/her house,few people know how to keep them for as long as possible .This may be done by keeping in mind a few simple facts.
2. An important thing to remember about cut flowers is that they are sensitive to temperature.For example,studies have shown that cut carnations（康乃馨）retain their freshness eight times lon-ger when kept at 12℃than when kept at 26℃．Keeping freshly harvested flowers at the right tem-peratures is probably the most important aspect of flower care.
3. Flowers are not intended by nature to live very long.Their biological purpose is simply to at-tract birds or insects,such as bees,for pollination（授粉）.After that,they quickly dry up and die. The process by which flowers consume oxygen and produce carbon dioxide（二氧化碳）, called respiration（呼吸）,generates the energy the flower needs to give the flower its shape and color. The making of seeds also depends on this energy.While all living things respire,flowers have a high level of respiration.A result of all this respiration is heat,and for flowers the level of heat relative to the mass of the flower is very high.Respiration also brings about the eventual death of the flower. Thus the greater the level of respiration,the sooner the flower dies.
4. How,then,to control the rate at which flowers die?By controlling respiration.How is respi-ration controlled?By controlling temperature .We know that respiration produces heat,but the re-verse（相反的过程）is also true. Thus by maintaining low temperatures , respiration is reduced and the cut flower will age more slowly.
5. Another vital factor in keeping cut flowers is the quality of the water in which they are placed. Flowers find it difficult to“drink”water that is dirty or otherwise polluted.Even when water looks and smells clean,it almost certainly contains harmful substances that can endanger the flowers. To rid the water of these unwanted substances, household chlorine bleach（漂白剂）can be used in small quantities.It is recommended that 15 drops of chlorine bleach(at 4%solution)be add-ed to each litre of water. The water and solution should also be replaced each day.

A few simple facts will help you keep cut flowers________.
A: by keeping its original shape and color
B: in the life of cut flowers
C: to produce carbon dioxide
D: for as long as possible
E: by controlling temperature
F: to replace the water and solution every day