根据短文内容.从短文后的选项中选出能填入空白处的最佳选项.选项中有两处为多余选项. Active ＆ Passive Transport Recall that all living things are made up of tiny units called cells, and that -cells are surrounded by a covering called a m 题目和参考答案——青夏教育精英家教网—

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根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两处为多余选项。

Active ＆ Passive Transport

　　Recall that all living things are made up of tiny units called cells, and that -cells are surrounded by a covering called a membrane (膜)．The membrane allows things to move in and out of the cell, and it also controls what can get through．　　1　　 They must have water, oxygen, sugar, sodium, potassium (钾) , and a variety of other minerals．The body has to have a delivery system to get these materials where they need to go．In addition, every cell produces waste materials that it needs to get rid of．　　2　　

　　Just like cars, trucks, and other vehicles form a transport system for the pick up and delivery of materials out in the world, the body has a transport system, too．　　3　　

　　Passive transport is easiest for the cells because they don't need to use any energy to make it happen．Diffusion (扩散) is the simplest and most common form of passive transport．

　　During the diffusion process, tiny particles (微粒) of the materials that need to be delivered to the cells are spread through either a gas (like oxygen) or a liquid (like water)．　　4　　Osmosis (渗透作用) is a unique form of passive transport that allows water to pass through the cell membrane, but keeps most other materials out．

　　Active transport is used when the concentration of materials inside the cell is high, and the cell needs to push materials out to areas of low concentration of the materials．Unfortunately, this kind of transport requires the cell to work against the natural direction of diffusion, so the cell uses up energy．　　5　　 They pump sodium out of their cells and pull potassium in．Although they must use energy in this process, doing so allows them to thrive (成长)．

A．Areas with high concentrations of the materials slowly diffuse them to areas of low concentration．

B．Cells need many kinds of materials in order to survive．

C．One example of this is the way that nerve cells work．

D．There are two kinds of transport：active transport, and passive transport．

E．Passive transport is much more essential than active transport．

F．The body has to have a method of waste collection and disposal．

G．Then the cell usually needs extra energy to make up for it．

答案：1．B;2．F;3．D;4．A;5．C

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根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

　　　　1　　 Such as runny noses, sore throats, nothing quite like the common cold to make you feel miserable．But experts believe that there is no link between cold weather and catching colds．　　2　　

　　Internal Medicine expert, Dr Meenakshi Jain of Max Hospital says, “One reason could be that people are likely to stay indoors, so the virus can spread easily．　　3　　”

　　The common cold is a viral infection that can be caused by any of up to 250 strains of virus, the most common group of which are the rhinovirus that hit the nose．

　　　　4　　 “They are transmitted through the nose respiratory passages, by touch, and by contact with airborne particles that are created by sneezing or coughing,” says Dr Jain．

　　There is no cure for the common cold and antibiotics are of no help．However, there are some precautions which can help：

　　　　5　　 In this case, you can protect your hands from getting germs．

　　Don’t touch your eyes, nose and mouth, which can limit your chances of infection．

　　Don’t share drinking glasses or utensils with anyone as this will prevent the spread of the virus．

　　Make sure to eat enough fruits to boost your immune system．
A．Also the virus thrives in humidity．

B．Drink lots of fluids to avoid dehydration．

C．They are responsible for anywhere between a third and half of all common colds．

D．Get enough sleep and you’ll certainly feel better．

E．So why are we particularly vulnerable(脆弱的)this season？

F．Wash your hands regularly．

G．It’s winter and you have probably noticed germs are everywhere．

任务型阅读。根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项，

　　Do you sweat, chew your pencil, and feel butterflies in your stomach as your teacher hands out a test? A lot of people get upset when it’s time to take a test．　　1　　 In fact, sometimes a little stress is a good thing for you．

　　Here are some tips for taking tests：

　　●　　2　　 It sounds like a no-brainer(不用动脑的事), but if you’re sure of the information, you’ll have less reason to be worried．

　　●Get enough sleep the night before the test．　　3　　 In a scientific study, people who got enough sleep before taking a math test did better than those who stayed up all night studying．

　　●　　4　　 Once you have the test paper in front of you, read over the entire test, checking out how long it is and all the parts that you are expected to complete．This will allow you to estimate how much time you have for each part and ask the teacher any questions．If something seems unclear before you start, don’t worry：ask．

　　●Relax．　　5　　 Of course you can’t get up and move around in the middle of a test, but you can wiggle(扭动)your fingers and toes, take four or five deep breaths, or picture yourself on a beach or some calm place．

　　These tips should help most people, but some can get serious test-taking error．If you’re one of them, you may need to talk to a parent or teacher for help．

A．Read the test through first．

B．Be sure you’ve studied properly．

C．Focus on dealing with each question personally．

D．It’s natural to feel some stress about taking tests．

E．Your memory will be much better if you’ve had enough rest．

F．As the teacher hands out the test, be sure you know what’s expected of you．

G．If you’re so nervous that you can’t think of anything, you might need a mini-break．

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项．选项中有两项为多余选项．

　　Have you ever seen an animal being mistreated(虐待)? Seeing a pet or wild animal get hurt might make you sad, angry, or afraid．1．________ In fact, the good news is that everyone-including you-can be a helping hand for animals．

　　Keep your eyes and ears open．2．________ Watch for changes in the way they look or act．Look out for animals who：

　　★have cuts or other bruises(伤痕)

　　★avoid or attack people when they come close

　　★are too thin

　　★are missing fur

　　★are almost always left outside

　　These signs don't necessarily mean a pet has been hurt on purpose, but they shouldn't be ignored．If you see any of these signs, set them down．3．________ What did you see or hear? Where? When? Were other people around?

　　4．________ Never move an injured animal! Ask a parent, teacher, or other adult you trust for help．Find out whether the injured animal in your town can be saved by animal shelters or police．Keep their phone numbers at hand．If the person mistreating animals is a friend or family member, tell an adult you trust．

　　Speak up．Let other kids know what to do if they see an animal being hurt．Using the information above, make posters to hang or flyers(传单)to hand out at school．Include the phone numbers of the police department or animal shelters who can save the injured animals．

　　5．________ They need us to speak up for them．

A．Report it．

B．Ask others for help．

C．Animals are friends of human beings．

D．Get to know pets in your neighborhood．

E．You might think there's nothing you can do．

F．Remember, animals can't speak for themselves．

G．Or if you see someone hurting an animal, write down the details．

根据短文内容，从短文后面的选项中选出能填入空白处的最佳选项。选项中有两项为多余项.

What to do if you and your teacher don’t get along

If you’re having problems with a teacher, try to find out why. 1.

Before you try to get out of a class you don’t like, here are a few things you can try to make you feel better.

● Meet with the teacher and try to talk to him or her. 2. For example, “ I can’t learn in class when I feel like that I can’t take part it.” See if you can work it out between the two of you.

● Ask yourself, “ What can I learn from this teacher?” You have to remember that he or she is very helpful and really know something in a certain field. 3.

● Talk to the students who are doing well in the class and ask them for some advice. If you’re too shy to talk to another student, try to follow his or her actions in the classroom.

● If your relationship problems can’t be solved in school, tell your parents. 4.

Teachers are there for more than just homework, and they know more than just their subjects. 5. There will always be a few teachers that you will always remember and who might change your life forever.

A. They are very considerate.

B. Tell his or her what’s on your mind.

C. They will tell you how to act as a student.

D. Do you hate the subject or just dislike the teacher?

E. Let them meet with your teacher to try to work it out.

F. Try to understand and accept your teacher’s personality.

They can help you to become a lifelong learner

第二节（共5小题；每小题2分，满分10分）

　　根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

　　In 1990 a report was published about what the earth might be like 20 years from then on. 71 According to the report,the picture of the earth in the year 2010 is not a pleasant one. 72 The population could be as large as 6300 million,almost 2150 million more than in 1985.More people would move into cities ,especially cities in developing countries.Cities like Cairo and Jakarta probably would each have 15 million by then.

　　 73 Farmers will grow 90% more food than they did in 1985,but most of the increase would be in countries that already produce enough food for their people. 74 Poor farming ways are destroying large areas of crop land,changing farms into deserts.More farmland is lost as cities become larger and more houses are built.Air pollution will get worse as industrial countries burn more coal and oil.Many of the world's forests could disappear as more and more trees are cut down.Energy will continue to be a serious problem. 75 They only workde out the situation that exists today.By changing the situation,by settling the problems,the picture can be changed.There is still time for the nations of the world to work out a plan of action.But they warned that waiting too long to make de cisions would greatly reduce the chances of success.

A．Food production will increase,but not enough to feed all the people.

B．The report was a result of a three - year study.

C．Later on,more reports came out one by one.

D．The world will be more crowded because the population will continue to grow.

　　E.Experts believe enough food will be produced in developing countries very soon.

　　F.The experts say their picture of the earth for the year 2010 may be wrong.

G.Little increase is expected in South Asia,Africa and the Middle East.

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