Yawning sends out certain messages -either “Oh ,this movie is so boring” or “I probably need to get some sleep”. But did you know that a yawn can also help your brain to cool down when it is overheated?
A new study, led by a research team at Princeton University, has indicated that yawning could be the brain’s natural way of regulating temperature. People yawn more often when the temperature outdoors is lower than their body temperature but are less likely to yawn when it is hotter outdoors, according to Sciencedaily. com.
The research team did an experiment on 160 people, 80 in summer and 80 in winter, to examine how often they yawned at different air temperatures. The study found that people yawned more often in winter than in summer. Scientists say that when the air temperature is lower outside the body, there is heat exchange between the overheated brain and the cool air. But when the air temperature is higher than or equal to the body, people are less likely to yawn because the hot air they breathe in will make the brain even hotter.
When people yawn, their jaw is also stretched ,which increases blood flow and may also help cool the brain
The study showed that the amount someone yawned could be related to the amount of time they spent outside. The longer they spent outside in summer, the less they yawned. Nearly 40 percent of participants yawned within their first five minutes outside, but after that the percentage was reduced to less than 10 percent.
However, the result was the opposite in winter. The number of people who yawned increased when they spent more than five minutes outdoors. But the change was only slight compared to summertime.
According to Gallup, this is the first report to show that yawning frequencies change depending on season. This could help us to understand better the way our brains work. It may also help us understand the reason why frequent yawning can sometimes be a sign of brain disease.
【小題1】The purpose of the experiment is ______.
A. to prove people yawn in winter and in summer equally |
B. to indicate brain can regulate temperature naturally |
C. to find the frequency of people’s yawning |
D. to show the real reason why people yawn |
A. longer outdoor summertime results in more yawns |
B. yawning frequency changes with outdoor time |
C. yawning frequency increases with outdoor time |
D. longer outdoor wintertime leads to fewer yawns |
A. Yawning Is A Sign of Brain Disease |
B. Yawning Carries Some Information |
C. Yawning Benefits Your Body |
D. Yawning Cools Your Brain |
【小題1】C
【小題2】B
【小題3】A
【小題4】D
解析試題分析:本文介紹了大腦調(diào)節(jié)溫度的自然方法是打呵欠。當(dāng)體溫高于室溫時,人們打呵欠的頻率會增加,反之會降低,同時,打呵欠的頻率變化取決于季節(jié),夏季時人們在戶外時前五分鐘有近40%的參加實驗的人會打呵欠,之后會降到不到10%,而冬季前五分鐘打呵欠的人比夏季多,但之后和夏季的數(shù)據(jù)只有輕微變化。
【小題1】細(xì)節(jié)題:根據(jù)第三段中“ to examine how often they yawned at different air temperatures.”檢查在不同的溫度下打呵欠的頻率。故選C。
【小題2】推理題:閱讀第五第六段可知在戶外打呵欠的頻率有所改變。夏季時人們在戶外時前五分鐘有近40%的參加實驗的人會打呵欠,之后會降到不到10%,而冬季前五分鐘打呵欠的人比夏季多,但之后和夏季的數(shù)據(jù)有輕微變化。故選B。
【小題3】細(xì)節(jié)題:根據(jù)第二段中“ People yawn more often when the temperature outdoors is lower than their body temperature”當(dāng)室外溫度低于體溫時人們會更多地打呵欠。故選A。
【小題4】推理題:閱讀文章可知第二段中“A new study, led by a research team at Princeton University, has indicated that yawning could be the brain’s natural way of regulating temperature”普林斯頓大學(xué)的一個研究小組的一項最新研究表明打呵欠是大腦調(diào)節(jié)溫度的自然方式,是文章主旨,全文圍繞這一主題展開舉例論述。故選D。
考點:考查科普類閱讀
科目:高中英語 來源: 題型:閱讀理解
Redwood trees are the tallest plants on the earth,reaching heights of up to 100 meters.They are also known for their longevity,typically 500 to 1000 years,but sometimes more than 2000 years.A hundred million years ago,in the age of dinosaurs,redwoods were common in the forests of a much more moist and tropical North America.As the climate became drier and colder,they declined to a narrow strip along the Pacific coast of Northern Califomia.
The trunk of redwood trees is very strong and usually forms a single straight column.It is covered with a soft bark.This bark can be pretty thick,well over two feet in the more mature trees.It gives the older trees a certain kind of protection from insects,but the main benefit is that it keeps the center of the tree harmless from moderate forest fires because of its thickness.This fire resistant quality explains why the giant redwood grows to live that long.While most other types of trees are destroyed by forest fires,the giant redwood actually prospers because of them.
Moderate fires will clear the ground of competing plant life,and the rising heat dries and opens the ripe fruit of the redwood,releasing many thousands of seeds onto the ground below.
New trees are often produced from shoots,little baby trees,which form at the base of the trunk.These shoots grow slowly,fed by the root system of the “mother’’ tree.When the main tree dies,the shoots are then free to grow as full trees,forming a “fairy ring” of trees around the original tree.These trees,in turn,may give rise to more shoots,and the cycle continues.
【小題1】Why were redwood trees easier to find in the forests of North America millions of years ago?
A.The trees were taller and stronger. |
B.The soil was softer for seeds to develop. |
C.The climate there was warmer and wetter. |
D.The temperature was lower along the Pacific coast. |
A.It allows redwood trees to bear seeds. |
B.It prevents redwood trees from attack by insects. |
C.It helps redwood trees absorb water in the air. |
D.It makes redwood trees more beautiful and appealing. |
A.They have heavy and straight tree trunks. |
B.They are properly watered and catered to. |
C.They are more resistant to fire damage than other trees. |
D.They produce many young trees to maintain their life cycle. |
A.By killing an old tree. | B.By connecting root systems. |
C.By inserting holes into old trees. | D.By surrounding a mature tree. |
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科目:高中英語 來源: 題型:閱讀理解
Chinese scientists have found a new way to use cells found in human urine (尿液)that could aid in the treatment of a range of nerve disorders.That is a new technique for reprogramming cells in human urine into nerve progenitor cells that can grow into multi-functional nerve and brain cells.
The technique is expected to be used in the study and treatment of nerve disorders such as Parkinson's disease, Alzheimer's disease and other nerve disorders.
Pei Duanqing, a professor at Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, said his research team has combined an episomal system to deliver reprogramming factors with a chemically defined culture medium to reprogram kidney epithelial(腎表皮) cells in urine into NPCs.
These NPCs, normally only found in the human brain, were later proven to be transgene-free and self-renewing, he said.
"These nerve and brain cells can survive for up to one month when transplanted into the brain of a newborn rat," said Pei. "My team is working hard to understand why our experimental condition allowed the urine cells to become NPCs, because we want to improve the technique and make it more efficient".
Scientists have long searched to treat and study neural disorders by obtaining and transplanting neural stem cells. However, the previous method of getting and using cells from either fetal (胎兒)or adult human tissue remains challenging due to ethical concerns and immune system rejections, he said.
Pei hopes the discovery will be used to generate NPCs from patients with nerve disorders such as Parkinson's disease. "These NPCs from patients may help us discover new drugs for these diseases."
"It is a remarkable advance in the stem cell field. The results and methods obtained from this study will be of great value and significance to the field, " said Fred Gage,a professor with the Salk Institute for Biological Studies.
【小題1】What is the passage mainly about?
A.NPCs are beneficial in treating human diseases. |
B.Chinese scientists succeeded in making NPCs from human urine. |
C.Chinese scientists have found cures for all diseases. |
D.A new technique was used to study the use of human urine |
A.make more contributions to medical study |
B.discover another new technique |
C.make the technique more perfect |
D.treat more patients suffering from bad diseases |
A.The ethical comcerns and immune system refusal |
B.The difificulties in getting cells from human. |
C.The under-developed techniques in medical science. |
D.The lack of financial support from the government. |
A.the new technique will be developed in science |
B.the results and methods will be applied to treating cancers |
C.the study will give a major push to the stem cell field |
D.the mew technique will bring great profis |
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科目:高中英語 來源: 題型:閱讀理解
Bad teeth may be painful and it’s getting worse without treatment. They can even ruin your life. Illness of the teeth can find its way into the blood system. This can increase the chances of a heart disease or other illnesses.
Experts say good care for teeth should start at birth. Mothers’ milk is the best food for the healthy development of teeth.
But dentists say a baby’s mouth and early teeth should be cleaned after each feeding. Use a cloth with a little warm water. Do the same if a baby is fed with a bottle. Experts say if you decide to put your baby to sleep with a bottle, give him only water.
When baby’s teeth begin to appear, you can clean them with a wet toothbrush. Dentists say it is important to find soft toothbrushes made especially for babies and to use them very gently. Young children often eat toothpaste (牙膏) when they brush, so they should be carefully watched when they brush their teeth.
Parents often ask what effect thumb sucking (咬手指) might have on their baby’s teeth. Experts generally agree that this is fine early in life. Most children stop sucking their thumbs by the age of four. If it continues, parents should talk to their children’s dentist or doctor.
Dentists say children should have their first dental visit by the time they are one year old. They say babies should be examined when their first teeth appear usually at around six months.
【小題1】Why should people pay attention to teeth problems?
A.They can cause other illnesses. |
B.They will bring bad luck. |
C.They will bring the family much trouble. |
D.They usually last a long time. |
A.he begins to speak | B.he has his first tooth |
C.he was born | D.he is fed with bottle milk |
A.toothache | B.parents’ trouble | C.thumb sucking | D.experts’ advice |
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科目:高中英語 來源: 題型:閱讀理解
(2013·高考安徽卷,B)Using too much water or throwingrubbish into our rivers are clear ways that humans can put our water supply in danger,but we also affect our water supply in less obvious ways.You may wonder how paving(鋪砌) a road can lead to less useable fresh water.A major part of the water we use every day is groundwater.Groundwater does not come from lakes or rivers.It comes from underground.The more roads and parking lots we pave,the less water can flow into the ground to become groundwater.
Human activity is not responsible for all water shortages(短缺).Drier climates are of course more likely to have droughts(干旱) than areas with more rainfall,but in any case,good management can help to make sure there is enough water to meet our basic needs.
Thinking about the way we use water every day can make a big difference,too.In the United States,a family of four can use 1.5 tons of water a day! This shows how much we depend on water to live,but there’s a lot we can do to lower the number.
You can take steps to save water in your home.To start with,use the same glass for your drinking water all day.Wash it only once a day.Run your dishwasher (洗碗機)only when it is full.Help your parents fix any leaks in your home.You can even help to keep our water supply clean by recycling batteries instead of throwing them away.
【小題1】Which of the following is most likely to lead to less groundwater?
A.Using river water. |
B.Throwing batteries away. |
C.Paving parking lots. |
D.Throwing rubbish into lakes. |
A.All water shortages are due to human behavior. |
B.It takes a lot of effort to meet our water needs. |
C.There is much we can do to reduce family size. |
D.The average family in America makes proper use of water. |
A.show us how to fix leaks at home |
B.tell us how to run a dishwasher |
C.prove what drinking glass is best for us |
D.suggest what we do to save water at home |
A.Why paving roads reduces our water |
B.how much we depend on water to live |
C.why droughts occur more in dry climates |
D.how human activity affects our water supply |
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科目:高中英語 來源: 題型:閱讀理解
Europe’s deadly outbreak of a rare form of E. coli bacteria (大腸桿菌) has brought new attention to food safety issues. One of the problems when people get sick from food is that the simplest question is often difficult or even impossible to answer. Just what did the people eat that made them sick?
Of course, one way to avoid these medical mysteries is to keep dangerous organisms out of the food supply. This is easier said than done, but scientists keep looking for new ways.
Scientists in the United States have developed an experimental system that uses a high-tech optical scanner. The system is designed to identify the presence of contaminants(致污物) like soil or animal waste on fresh produce. These can be sources of E. coli. E. coli bacteria naturally live in the intestines(腸) of humans and many animals. Most kinds of E. coli are harmless but some can make people sick.
The new scanner can also show damage and imperfections that might make the produce unappealing to shoppers.
Scientists designed the system at a Department of Agriculture research center in Beltsville, Maryland. Moon Kim of the Agricultural Research Service led the team.
MOON KIM: “We were requested, we were asked, to develop a method to detect contamination in produce. So we started with the apple as the model sample.”
The scanner uses a high-speed camera placed over the conveyer belt that moves the produce along. As the apples move along the belt, the scanner captures images of each piece of fruit.
Moon Kim says the team hopes the system will be available before long.
MOON KIM: “We are targeting for development in commercial plants for the next several years.”
The scanner can direct a sorting machine to separate the bad apples from the good ones. The system is currently able to show the surface of only half the apple as it speeds by. The inventers hope to improve the process so it can show the whole surface.
【小題1】What is the main topic of the text?
A.Bacteria. | B.A high-tech scanner. | C.A camera | D.Food safety. |
A.broke out all over the world | B.comes from soil or animal waste |
C.is extremely harmful to health | D.does not cause illness |
A.can help to sort out different fruits |
B.make the produce appeal to shoppers |
C.can only capture images of the whole apple |
D.can identify the presence of contaminants |
A.The scanner needs to be improved. |
B.The scanner will be available in the next several years. |
C.Moon Kim is unwilling to develop the scanner. |
D.The scanner is connected to a sorting machine. |
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科目:高中英語 來源: 題型:閱讀理解
The need to feed a growing population is putting much pressure on the world's supply of water. With 97% of the world's water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage(短缺)seems strange to someone fortunate enough to live in a high rainfall country, many of the world's agricultural industries experience constant water shortages.
Although dams can be built to store water for agricultural use in dry areas and dry seasons, the costs of water redistribution(重新分配)are very high. Not only is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys(山谷)are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water may flow easily through pipes to fields, but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements.
This is particularly troubling for countries with agricultural industries in areas dependent on irrigation (灌溉). In Texas, farmers' overuse of irrigation water has resulted in a 25% reduction of the water stores. In the Central Valley area of southwestern USA, a huge water engineering project provided water for farming in dry valleys, but much of the water use has been poorly managed.
Saudi Arabia's attempts to grow wheat in desert areas have seen the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.
【小題1】From the first two paragraphs we learn that________.
A.much of the world's water is available for use |
B.people in high rainfall countries feel lucky |
C.water can be easily carried through pipes across the world |
D.the costs of water redistribution should be considered |
A.The water stores in Texas have been reduced by 75%. |
B.Most industries in the world suffer from water shortages. |
C.The underground water in Saudi Arabia might run out in 50 years. |
D.Good management of water use resulted from the project in the Central Valley. |
A.Steps to improving water use management. |
B.Ways to reduce the costs of building dams. |
C.Measures to deal with worldwide water shortages. |
D.Approaches to handling the pressure on water supply. |
A.water supply and increasing population |
B.water use management and agriculture |
C.water redistribution and wildlife protection |
D.water shortages and environmental protection |
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科目:高中英語 來源: 題型:閱讀理解
About ten men in every hundred suffer from color blindness in some way. Women are luckier, only about one in two hundred if affected in this matter. Perhaps, after all, it is safer to be driven by a woman.
There are different forms of color blindness. In some cases a man may not be able to see deep red. He may think that red, orange and yellow are all shades of green. Sometimes a person can’t tell the differences between blue and green. In rare cases an unlucky man sees everything in shades of green--- a strange world in deed.
Color blindness in human beings is a strange thing to explain. In a single eye there are millions very small things called “cones”. These help us see in a bright day and tell the differences between colors. There are also millions of “rods”, but these are used for seeing when it is nearly dark. They show us shapes(形狀) but not color. Some insects have favorite colors. Mosquitoes like blue but do not like yellow. A red light will not attract insects but a blue lamp will. In similar way human being also have favorite colors. Yet we are lucky. With the aid of cones in our eyes we can see many beautiful colors by day and with the aid of the rods we can see shapes at night. One day we may even learn more about the invisible colors around us.
【小題1】The passage is mainly about ______.
A.color and its surprising effects on drivers |
B.women being luckier than man in that fewer of them are color blind |
C.danger caused by color blindness |
D.color blindness and how our eyes tell different colors and shapes |
A.tell different colors | B.see in weak light |
C.tell different shapes | D.tell orange from yellow |
A.Women are more careful. |
B.There are fewer color blind women. |
C.Women are fonder of driving than men. |
D.Women are weaker but quicker in thinking. |
A.Not all of them have the same problem in recognizing colors. |
B.None of them can see deep red but all can tell blue from green. |
C.None of them can tell blue from green but all can see deep red. |
D.All of them are lucky enough to see everything in shades of green. |
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科目:高中英語 來源: 題型:閱讀理解
“If you want to see a thing well, reach out and touch it!”
That may seem a strange thing to say. But touching things can help you to see them better.
Your eyes can tell you that a glass ball is round. But by holding it in your hands, you can feel how smooth and cool the ball is. You can feel how heavy the glass is. When you feel all these about the ball, you really see it. With your skin, you can feel better. For example, your fingers can tell the difference between two coins in your pocket. You can feel a little drop of water on the back of your hand, too. You can even feel sounds against your skin. Have you ever wanted to know why some people like very loud music? They must like to feel the sounds of music.
All children soon learn what “Don't touch!”means. They hear it often. Yet most of us keep on touching things as we grow up. In shops, we touch things we might buy: food, clothes. To see something well, we have to touch it. The bottoms of our feet can feel things, too. You know this when you walk on warm sand, cool grass or a hard floor. All feel different under your feet.
There are ways of learning to see well by feeling. One way is to close your eyes and try to feel everything that is touching your skin. Feel the shoes on your feet, the clothes on your body, the air on your skin. At first, it is not easy to feel these things. You are too used to them!
Most museums are just for looking. But today some museums have some things to touch. Their signs say, “Do touch!” There you can feel everything on show.
If you want to see better, reach out and touch. Then you will really see!
【小題1】By touching things, .
A.you will have a strange feeling |
B.you will learn how to reach out your hand |
C.you can learn more about them |
D.you can tell what colors they really are |
A.Touching by Feeling | B.To See or to Feel |
C.To See Better—Feel | D.Ways of Feeling |
A.Your fingers. | B.Your eyes. | C.Your skin. | D.Your back. |
A.Sounds. | B.Darkness. | C.Water. | D.Coins. |
A.Touching is helping us to see better. |
B.Our skips may help us enjoy music. |
C.People don't have to learn to feel. |
D.Visitors can't feel the things on show in any museums. |
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