题目
题型:不详难度:来源:
If blood is red, why are veins(静脉) blue?
Actually, veins are not blue at all. They are more of a clear, yellowish color. Although blood looks red when it’s outside the body, when it’s sitting in the vein near the surface of the skin, it’s more of a dark reddish purple color. At the right depth, these blood-filled veins reflect less red light than the surrounding skin, making them look blue by comparison.
Which works harder, you heart or your brain?
That kind of depends on whether you’re busy thinking or busy exercising. Your heart works up to three times harder during exercise, and shifts enough blood over a lifetime to fill a supertanker. But in the long run, your brain probably tips it, because even when you’re sitting still your brain is using twice as much energy as your heart, and it takes four to five times as much blood to feed it.
Why do teeth fall out, and why don’t they grow back in grown-ups?
Baby (or “milk”) teeth do not last long; they fall out to make bigger room for bigger, stronger adult teeth later on. Adult teeth fall our when they become damaged, decayed and infected by bacteria. Once this second set of teeth has grown in, you’re done. When they’re gone, they are gone. This is because nature figures you’re set for life, and what controls regrowth of your teeth switches off.
Do old people shrink as they age?
Yes and no. Many people do get shorter as they age. But, when they do, it isn’t because they’re shrinking all over. They lose height as their spine(脊柱) becomes shorter and more curved due to disuse and the effect of gravity(重力). Many (but not all) men and women do lose height as they get older. Men lose and average of 3-4 cm in height as they age, while women may lose 5 cm or more. If you live to be 200 years old, would you keep shrinking till you were, like 60 cm tall, like a little boy again? No, because old people don’t really shrink! It is not that they are growing backwards ----- their legs, arms and backbones getting shorter. When they do get shorter, it’s because the spine has shortened a little. Or, more often, become more bent and curved.
Why does spinning make you dizzy(眩晕的)?
Because your brain gets confused between what you’re seeing and what you’re feeling. The brain senses that you’re spinning using special gravity-and-motion-sensing organs in your inner ear, which work together with your eyes to keep your vision balance stable. But when you suddenly stop spinning the system goes out of control, and your brain thinks you’removing while you’re not.
Where do feelings and emotions come from?
Mostly from an ancient part of the brain called the limbic system. All mammals have this brain area ----- from mice to dogs, cats, and humans. So all mammals feel basic emotions like fear, pain and pleasure. But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animal on this planet.
If exercise wears you out, how can it be good for you?
Because our bodies adapt to everything we do to them. And as far as your body is concerned, it’s “use it, or lose it”! It’s not that exercise makes you healthy, it’s more that a lack of exercise leaves your body weak and easily affected by disease
小题1:What is the color of blood in a vein near the surface of the skin?
A.Blue | B.Light yellow |
C.Red | D.Dark reddish purple |
A.Because their spine is in active use. |
B.Because they are more easily affected by gravity. |
C.Because they keep growing backwards. |
D.Because their spine becomes more bent. |
A.In the long run, our brain probably works harder than our heart. |
B.When our brain senses the spinning, we will feel dizzy. |
C.The brains of the other mammals are as complex as those of humans. |
D.Our feelings and emotions come from the most developed area in our brain. |
A.To give advice on how to stay healthy. |
B.To provide information about our body. |
C.To challenge new findings in medical research. |
D.To report the latest discoveries in medical science. |
答案
小题1:D
小题2:D
小题3:A
小题4:B
解析
小题1:根据第一段第二句Although blood looks red when it’s outside the body, when it’s sitting in the vein near the surface of the skin, it’s more of a dark reddish purple color.很容易判断出选D。
小题2:根据第四段最后一句Or, more often, become more bent and curved.可以判断选D。
小题3:根据第二段最后一句But in the long run, your brain probably tips it, because even when you’re sitting still your brain is using twice as much energy as your heart, and it takes four to five times as much blood to feed it.可知A项正确。通过第五段最后一句But when you suddenly stop spinning the system goes out of control, and your brain thinks you’removing while you’re not可知当我们突然停止旋转时才会感到眩晕,所以B项错误;通过第六段最后一句But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animal on this planet.可知C,D两项错误。
小题4:本篇的写作意图就是让我们了解我们的身体,为我们提供一些基本的信息,故B项正确。
核心考点
试题【Below is a selection from a popular science book. If blood is red, why are veins】;主要考察你对题材分类等知识点的理解。[详细]
举一反三
If the CRF seems to be a smart idea, that"s because Lee is not merely a seasoned salesperson but also head of a marketing department that has business relations with big names such as Levi"s and Sony. That idea surely results in the imagination at work when it comes to making different flavored(味道)chocolates.
The CRF"s produce is "green". made within the country and divided into 10 lines, with the Alcohol Series being the most popular. The Exotic Series一with Sichuan pepper, red bean (豆).cheese and other flavors一also does well and is fun to taste. And for chocolate snobs,who think that they have a better knowledge of chocolate than others, the Connoisseur Series uses cocoa beans from Togo, Cuba, Venezuela , and Ghana, among others.
小题1:What is good about chocolate?
A.It serves as a suitable gift. |
B.It works as an effective medicine. |
C.It helps improve the state of mind. |
D.It strengthens business relations. |
A.He knows the importance of research. |
B.He learns form shops of similar types. |
C.He has the support of many big names |
D.He has a lot of marketing experience. |
A.The Connoisseur Series. |
B.The Exotic Series. |
C.The Alcohol Series. |
D.The Sichuan Series. |
A.are particular about chocolate |
B.know little about cocoa beans |
C.look down upon others |
D.like to try new flavors |
Doctors don’t agree about the medical effects of cold-water swimming. Some are worried about the dangers of a condition in which the body’s temperature drops so slow that finally the heart stops. Other doctors, however, point out that there is more danger of a heart attack during summer swimming because the difference between the air temperature and the water tempreature is much greater in summer than in winter.
The Polar Bears themselves are satisfied with the benefits of cold-water swimming. They say that their favorite form of exercise is very good for the circulatory system (循环系统) because it forces the blood to move fast to keep the body warm. Cold-water swimmers usually turn bright red after a few minutes in the water. A person who turns blue probably has a very poor circulatory system and could not try cold-water swimming.
The main benefits of cold-water swimming are probably mental. The Polar Bears love to swim all the year round; they find it fun and relaxing. As one 70-year-old woman says, “When I go into the water, I pour my troubles into the ocean and let them float away.”
小题1:Doctors _________ .
A.have different ideas about the medical effects of cold-water swimming |
B.believe swimming is helpful both in summer and in winter |
C.enourage people to take part in cold-water swimming |
D.point out the possible danger of blood illness during cold-water swimming |
A.Polar bears are bears swimming in freezing water |
B.cold-water swimming can make the body temperature dangerously high |
C.you are healthy if cold-water swimming turns your skin color blue |
D.cold-water swimming causes more heart attack in summer than in winter |
A.it is an easy way to keep the body warm in winter |
B.they can stay young |
C.they find it enjoyable and interesting |
D.they might meet fewer troubles in life |
A.The Polar Bear is a club in which people swim to protect polar bears. |
B.The club members are all over 60 years old. |
C.There is no woman in the club. |
D.None of the above. |
A.the requirements of the Polar Bear Club |
B.a group of cold-water-swimming lovers |
C.the Polar Bears’ life in New York |
D.doctors’ ideas about cold-water swimming |
There are four main food groups altogether. The dairy group has food like milk, cheese and sour milk. The other three groups are the meat and fish group, the fruit and vegetable group, and the bread and rice group. Each meal should have at least one food from all four main groups. With all of these foods together, you will be given enough energy during the day.
It is easy to get into bad eating habits. You may eat your breakfast in a hurry to get to school on time or you may not have time for a good lunch. It may be easier to eat fish and chips for your supper all the time. But you will find yourself tired and you will not be able to think quickly.
Watching what you eat will help keep your body healthy and strong. It is also good to take some exercise. It will help you eat more if you take a walk or play games in the open air. Having good eating habits with some exercise is the key to your health.
小题1:According to the passage, which of the following diets do you think is the best one?
A.Eggs, tomatoes and chicken. | B.Milk, bread, cabbages and beef. |
C.Corn, fish, ice cream and pork. | D.Rice, beancurd, fish and chicken. |
A.every person needs food to grow well |
B.taking exercise can keep your body strong |
C.the right kind of food with exercise will keep you healthy |
D.enough energy helps people think more quickly |
But what is park-our? It is the art of using only your body to navigate from Point A to B in the least time possible, which involves besides leaping, climbing and sprinting, various unusual and complex movements to overcome barriers. Just like the James Bond in the movie Casino Royale? Bond jumps down from a roof to a windowsill and then runs several blocks over obstacles on the way. It is just because of Bond’s wonderful performances that the sport has become popular worldwide.
Yes, that’s pork-our, an extreme street sport aimed at moving from one point to another as quickly as possible, getting over all the obstacles in the path using only the abilities of the human body. Park-our is considered an extreme sport. As its participants dash around a city, they may jump over fences, run up walls and even move from rooftop to rooftop.
Park-our can be just as exciting and charming as it sounds, but its participants see much more in park-our than that.
To overcome all the obstacles on the course and in life is part of the philosophy(理念)behind park-our. This is the same as life. You must determine your destination, go straight, jump over all the barriers as if in park-our and never fall back from them in your life to reach the destination successfully. A park-our lover said, “I love park-our, because its philosophy has become my life, my way to do everything.”
Another philosophy we’ve learned from park-our is freedom. It can be done by anyone, at any time, anywhere in the world. It is a kind of expression of trust in yourself so that you earn energy and confidence.
小题1: Park-our has become popular throughout the world because of ________.
A.its founder, David Belle | B.the film, Casino Royale |
C.its risks and tricks | D.the varieties of participants |
A.streets | B.objects | C.barriers | D.roofs |
A.they can ask for help | B.they may choose to escape |
C.they should run to extremes | D.they must learn to survive |
A.It challenges human abilities. | B.It is a good but boring sport |
C.It needs special training | D.It is a team sport |
A.Sports and extremes. | B.Excitement and freedom. |
C.Dreams and success. | D.Self-confidence and freedom. |
Get on a bicycle and ride around your neighborhood. You may discover something new all around you. Stopping and getting off a bike is easier than stopping and getting out of your car. You can bike to work and benefit from the enjoyable exercise without polluting the environment. You don"t even have to ride all the way.
Folding bikes work well for people who ride the train. Just fold the bike and take it with you. You can do the same on an airplane. A folding bike can be packed in a suitcase. You can also take a common bike with you when you fly. But be sure to look for information by getting on airline websites. Not all airlines are bicycle-friendly to travelers.
Health Benefits of Bicycling:
It helps to prevent heart diseases and control your weight.
A 15-minute bike ride three times a week burns off five kilos of fat a year.
Bicycling can improve your mood.
Exercise like bicycling has been shown to make people feel better, more relaxed and self-confident.
Bicycling is healthier than driving.
小题1:From the passage, we know that bicycling is becoming very _______.
A.surprising | B.exciting | C.expensive | D.popular |
A.pollute the environment around | B.find something you didn"t notice |
C.go everywhere and use a little oil | D.get off your bike and begin to work |
A.get out of the car | B.take it onto a train |
C.put it in your purse | D.go on airline websites |
A.you can fold the bicycle | B.you will be friendly to others |
C.you will be more relaxed | D.you may get fatter and fatter |
A.Bicycling is an enjoyable exercise for people. |
B.Driving cars is healthier than riding bikes. |
C.Riding a bike pollutes your neighborhood. |
D.Common bikes are welcomed by all airlines. |
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