Which came first, the chicken or the egg? This is one of life’s __1__ questions and people have been debating about it for thousands of years. Now scientists believe they have solved this _2__. Researchers from Sheffield and Warwick Universities in England discovered the answer __3__. They used a super computer to observe the shell-making process while a new shell was __4__. Then they found one protein called OC17 that is __5__ for forming eggshell. This is only found inside a chicken’s body, which is proof that the _6__ came first. The team was __7__ looking at how animals and birds make eggshells but suddenly made their surprising __8__. The big question now is where chickens came from. The _9__ is from dinosaurs.
The research team said eggshells are one of nature’s most __10__ creations. Professor John Harding from the team told reporters: “Understanding how chickens make eggshells is fascinating in itself, but it can also be __11__ in designing new materials.” Eggshells are very lightweight but incredibly strong. Even the most up-to-date materials __12__ by the world’s top engineers can not produce anything as __13__ as an eggshell. Professor Harding added that __14__ eggshells could help to cure bone diseases and design materials for the construction industry.“Nature has found wonderful ways that __15__ for all kinds of problems in materials science and technology — we can learn a lot from them.” he said.
【小题1】
A.strangestB.bestC.oldestD.longest
【小题2】
A.puzzleB.storyC.historyD.idea
【小题3】
A.on purposeB.by chanceC.without hesitationD.at work
【小题4】
A.breakingB.changingC.disappearingD.forming
【小题5】
A.necessaryB.easyC.kindD.impossible
【小题6】
A.eggB.eggshellC.chickenD.dinosaur
【小题7】
A.obviouslyB.originallyC.thoughtfullyD.surprisingly
【小题8】
A.inventionB.mistakeC.statementD.discovery
【小题9】
A.answerB.researchC.keyD.egg
【小题10】
A.strangeB.ridiculousC.funnyD.amazing
【小题11】
A.hopefulB.helpfulC.respectfulD.colorful
【小题12】
A.boughtB.cutC.designedD.carried
【小题13】
A.brilliantB.ordinaryC.1ightD.strong
【小题14】
A.findingB.watchingC.studyingD.making
【小题15】
A.happenB.workC.waitD.look
Increasingly ,over the past ten years ,people—especially young people—have become aware of the need to change their eating habits ,because much of the food they eat ,particularly processed foods ,is not good for the health .As a result ,there has been a growing interest in natural foods :foods which do not contain chemical fertilizers ,widely used in farming today .
Natural foods ,for example ,are vegetables ,fruit and grain which have been grown in soil that is rich in organic(有机的)matter . In simple terms ,this means that the soil has been nourished by unused vegetable matter ,which provides it with essential vitamins and minerals. This in itself is a natural process compared with the use of chemicals and fertilizers , the main purpose of which is to increase the amount—but not the quality—of food grown in commercial farming areas .
Natural foods also include animals which have been allowed to feed and move freely in healthy grassland for cattle .Compare this with what happens in the mass production of poultry (家禽):there are battery farms ,for example ,where thousands of chickens live crowded together in one building and are fed on food which is little better than rubbish .Chickens kept in this way are not only tasteless as food; they also produce eggs which lack important vitamins .
There are other things of healthy eating which are now receiving increasing attention from experts on diet .Take ,for example ,the question of sugar .This is actually a non-essential food! Although another natural food ,such as honey ,can be used to sweeten food if this is necessary ,we can in fact do without it .It is not that sugar is harmful in itself .But it does seem to be addictive : the quantity we use has grown steadily over the last two centuries and in Britain today each person consumes an average of 200 pounds a year !Yet all it does is provide us with energy ,in the form of calories .There are no vitamins in it ,no minerals ,and no fibre .
It’s very important that nowadays fibre is considered to be an important part of a healthy diet .In white bread ,for example ,the fibre has been removed .But it is present in unrefined flour and of course in vegetables .It is interesting to note that in countries where the national diet contains large quantities of unrefined flour and vegetables ,certain diseases are comparatively not often seen .For this reason ,the importance is placed on the eating of wholemeal(没有去麸的面粉)bread and more vegetables by modern experts on “healthy eating”.
【小题1】People have become more interested in natural foods because            .
A.they want to keep fit
B.they want to taste all kinds of foods
C.natural foods are more delicious than processed foods
D.they want to return to nature
【小题2】Chickens raised in poultry farms are all of the following EXCEPT that           .
A.they are fed on food which is little better than garbage
B.they live in very crowed condition
C.the eggs they produce lack vitamins
D.they are allowed to move about and eat freely
【小题3】According to the passage,_________.
A.people need sugar to give them energy
B.sugar is bad for the health
C.the use of sugar is habit forming
D.sugar only sweetens food, but provides us with nothing useful
Answer the questions(根据短文内容回答下列问题)
Your Nose is Busy and Important
Your nose has many important jobs, and is always busy.
Smelling
Smelling helps you gather information about the world around you. A good scent (气体),like flowers, brings you pleasure. A bad scent, like smoke or sour milk, warns you of danger. Most things around you release scent particles (微粒) into the air. These invisible chemicals enter the nose when you breathe. Nerves in the nose send information to the brain to identify a smell. You are able to recognize thousands of smells.
Breathing
Most of the air you breathe enters through your nose. The nose uses hair and mucus (粘液) to clean dust and germs (细菌) out of the air. The air that enters your nose contains oxygen. Your body uses oxygen to unlock the energy in the food you eat.  Even when you sleep, your body needs energy to keep your heart beating and your brain working.
Tasting
Your nose helps you enjoy food. Flavor is a mixture of taste and smell. The smell of the food helps you identify what you are eating. The sense of smell contributes more to (贡献) food flavor than the sense of taste .When you are sick and have a stuffy nose, your food doesn’t taste as good because without smell, food loses most of its flavor.
Smell memory
Smells can bring back memories. Your brain uses a process to create a picture in your mind from the odors(气味)you smell. Smells can affect your feelings because the part of the brain that helps you identify smells is close to the area that affects your emotions, mood and memory. More smell memories are collected as you get older.
Your nose has many important jobs, and is more than just a smeller!
【小题1】How many important jobs does a nose do according to the passage? What are they?
【小题2】Smelling helps you recognize thousands of smells, doesn't it?
【小题3】What does the nose use to clean dust and germs out of air?
【小题4】What happens to your food if you are sick and have a stuffy nose?
【小题5】How do smells bring back memories?
【小题6】What do you think of your nose? Why do you think so?
Answer the questions(根据短文内容回答下列问题)
Your Nose is Busy and Important
Your nose has many important jobs, and is always busy.
Smelling
Smelling helps you gather information about the world around you. A good scent (气体),like flowers, brings you pleasure. A bad scent, like smoke or sour milk, warns you of danger. Most things around you release scent particles (微粒) into the air. These invisible chemicals enter the nose when you breathe. Nerves in the nose send information to the brain to identify a smell. You are able to recognize thousands of smells.
Breathing
Most of the air you breathe enters through your nose. The nose uses hair and mucus (粘液) to clean dust and germs (细菌) out of the air. The air that enters your nose contains oxygen. Your body uses oxygen to unlock the energy in the food you eat.  Even when you sleep, your body needs energy to keep your heart beating and your brain working.
Tasting
Your nose helps you enjoy food. Flavor is a mixture of taste and smell. The smell of the food helps you identify what you are eating. The sense of smell contributes more to (贡献) food flavor than the sense of taste .When you are sick and have a stuffy nose, your food doesn’t taste as good because without smell, food loses most of its flavor.
Smell memory
Smells can bring back memories. Your brain uses a process to create a picture in your mind from the odors(气味)you smell. Smells can affect your feelings because the part of the brain that helps you identify smells is close to the area that affects your emotions, mood and memory. More smell memories are collected as you get older.
Your nose has many important jobs, and is more than just a smeller!
【小题1】How many important jobs does a nose do according to the passage? What are they?
【小题2】Smelling helps you recognize thousands of smells, doesn't it?
【小题3】What does the nose use to clean dust and germs out of air?
【小题4】What happens to your food if you are sick and have a stuffy nose?
【小题5】How do smells bring back memories?
【小题6】What do you think of your nose? Why do you think so?
Answer the questions(根据短文内容回答下列问题)
Your Nose is Busy and Important
Your nose has many important jobs, and is always busy.
Smelling
Smelling helps you gather information about the world around you. A good scent (气体),like flowers, brings you pleasure. A bad scent, like smoke or sour milk, warns you of danger. Most things around you release scent particles (微粒) into the air. These invisible chemicals enter the nose when you breathe. Nerves in the nose send information to the brain to identify a smell. You are able to recognize thousands of smells.
Breathing
Most of the air you breathe enters through your nose. The nose uses hair and mucus (粘液) to clean dust and germs (细菌) out of the air. The air that enters your nose contains oxygen. Your body uses oxygen to unlock the energy in the food you eat.  Even when you sleep, your body needs energy to keep your heart beating and your brain working.
Tasting
Your nose helps you enjoy food. Flavor is a mixture of taste and smell. The smell of the food helps you identify what you are eating. The sense of smell contributes more to (贡献) food flavor than the sense of taste .When you are sick and have a stuffy nose, your food doesn’t taste as good because without smell, food loses most of its flavor.
Smell memory
Smells can bring back memories. Your brain uses a process to create a picture in your mind from the odors(气味)you smell. Smells can affect your feelings because the part of the brain that helps you identify smells is close to the area that affects your emotions, mood and memory. More smell memories are collected as you get older.
Your nose has many important jobs, and is more than just a smeller!
【小题1】How many important jobs does a nose do according to the passage? What are they?
【小题2】Smelling helps you recognize thousands of smells, doesn't it?
【小题3】What does the nose use to clean dust and germs out of air?
【小题4】What happens to your food if you are sick and have a stuffy nose?
【小题5】How do smells bring back memories?
【小题6】What do you think of your nose? Why do you think so?
Answer the questions(根据短文内容回答下列问题)
Your Nose is Busy and Important
Your nose has many important jobs, and is always busy.
Smelling
Smelling helps you gather information about the world around you. A good scent (气体),like flowers, brings you pleasure. A bad scent, like smoke or sour milk, warns you of danger. Most things around you release scent particles (微粒) into the air. These invisible chemicals enter the nose when you breathe. Nerves in the nose send information to the brain to identify a smell. You are able to recognize thousands of smells.
Breathing
Most of the air you breathe enters through your nose. The nose uses hair and mucus (粘液) to clean dust and germs (细菌) out of the air. The air that enters your nose contains oxygen. Your body uses oxygen to unlock the energy in the food you eat.  Even when you sleep, your body needs energy to keep your heart beating and your brain working.
Tasting
Your nose helps you enjoy food. Flavor is a mixture of taste and smell. The smell of the food helps you identify what you are eating. The sense of smell contributes more to (贡献) food flavor than the sense of taste .When you are sick and have a stuffy nose, your food doesn’t taste as good because without smell, food loses most of its flavor.
Smell memory
Smells can bring back memories. Your brain uses a process to create a picture in your mind from the odors(气味)you smell. Smells can affect your feelings because the part of the brain that helps you identify smells is close to the area that affects your emotions, mood and memory. More smell memories are collected as you get older.
Your nose has many important jobs, and is more than just a smeller!
【小题1】How many important jobs does a nose do according to the passage? What are they?
【小题2】Smelling helps you recognize thousands of smells, doesn't it?
【小题3】What does the nose use to clean dust and germs out of air?
【小题4】What happens to your food if you are sick and have a stuffy nose?
【小题5】How do smells bring back memories?
【小题6】What do you think of your nose? Why do you think so?
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