题干

   A calorie is a unit of energy, not a measure of weight or nutrient density. The calories you see on nutrition labels,however,are actually kilocalories. The calories on food packaging always refer to kilocalories, even though it just says “calories”. One kilocalorie is the amount of energy required to heat 1 kilogram of water by 1 degree Celsius. Calories in our food all come from one of the three nutrients: fats, carbohydrates and proteins.

In 1990, the U. S. government passed the Nutrition Labeling and Education Act, which means that before any packaged food in the U. S. hits the shelves, food scientists have to measure its nutrients and calories. One way to do this is using a tool called bomb calorimeter(弹氧热卡计). This tool directly measures the amount of energy that a food contains. To use this tool, scientists place the food in question in a sealed(密封的)container surrounded by water and heat it until the food is completely burned off. Scientists then record the rise in water temperature to determine the number of calories in the product.

Food scientists also rely on a calculation developed by the 19th-century U. S. chemist Wilbur Olin Atwater to indirectly estimate the number of calories in food products. Calorimeters don’t take into account that humans lose some calories through heat and feces(类便). Atwater’s experiments found that proteins and carbohydrates each have about 4 calories per gram and fats have 9 calories per gram.

However, some experts say that the Atwater system is outdated and inaccurate. A 2012 study found that the energy content of certain foods, such as nuts, could not be accurately calculated by the Atwater system. Besides, it does not take into account the digestive process, but assumes the complete conversion of nutrients to energy.

【小题1】What can we learn about the unit of energy on nutrition labels?
A.It actually means calories.
B.It refers to kilocalories.
C.It reads kilograms.
D.It employs degrees.
【小题2】What should be done to measure the amount of calories according to the calorimeter?
A.Heat the food in an open container until the food is completely burned off.
B.Take the calories through heat and feces into consideration.
C.Learn the calculation developed by Wilbur Olin Atwater.
D.Calculate the amount of energy in food products directly.
【小题3】How many calories does a food containing 10 grams of proteins and 5 grams of fats have according to the Atwater system?
A.About 40.B.About 45.
C.About 85.D.About 130.
【小题4】What would be the best title for the text?
A.How Are Calorie Counts Calculated?
B.Where do Calories Come from?
C.Can Nutrients Be Converted to Energy Totally?
D.Nutrients and Calories Listed on a Food Label
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同类题1

   Living near the ocean is good for health, but not a luxury all can afford. But those who can, certainly gain a lot of health benefits over common inland folks.

【小题1】 As we know, because people living near a coast get enough time to swim in the seawater, they naturally tend to be stronger. Physicians have been recommending visits to coasts that specialize in providing seawater cleansing treatment, which improves the immune system.

● Living near the ocean promotes physical activity. The seashore encourages outdoor activities like jogging on the sand, beach volleyball, scuba-diving, surfing, etc .【小题2】

● Fresh air helps get sleep. Fresh ocean air is composed of negatively charged ions that enable us to consume oxygen, adding to good health. These ions also aid in balancing the serotonin (血清素) level, which helps in feeling more relaxed. 【小题3】 Little by little, this leads to better sleep after spending a large amount of time near the ocean.

● Living near the ocean can help you absorb more vitamin

A.
【小题4】 Thus, natural sunlight, along with the sunrays which bounce back from the sand and the ocean, is an excellent supply for our everyday need for vitamin
A.

● Living near the ocean is helpful in meditation (冥想).

【小题5】 It helps the mind jolt (摇动) free from all worries of the past or the future. We get totally tuned into the present, and become calm, as we listen to the gradual rise and fall of the waves.
A.People living near a coast are healthier.
B.Sunshine is a major source of vitamin D.
C.How will living near the ocean help improve your health?
D. Just sit near the seashore and observe the waves moving back and forth.
D.This serves in leading an active lifestyle for people living near or on beaches.
E.Vitamin D helps you absorb calcium, maintaining a normal immune system.
F.Besides, when you listen to the sound of waves, it relaxes the mind to a very calm state.

同类题3

   The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid---we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴)native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water’s surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we,d need huge feet that we could bring up to our ears in order to create adequate w hitting. ’’

But fortunately there is an alternative : cornflour. By adding enough of this common thickening agent to water (and it does take a lot), you can create a “non-Newtonian” liquid that doesn’t behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子)in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick Liquid of cornflour.

Fun though all this may sound, it’s still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink--and take a shower afterward!

【小题1】Walking on water hasn’t become a reality mainly because humans______.
A.are not interested in it
B.have biological limitations
C.have not invented proper tools
D.are afraid to make an attempt
【小题2】What do we know about Basilicus basilicus from the passage?
A.It is light enough to walk on water.
B.Its huge feet enable it to stay above water.
C.It can run across water at a certain speed.
D.Its unique skin keeps it from getting wet in water.
【小题3】What is the function of the cornflour according to the passage?
A.To create a thick liquid.
B.To turn the water into solid.
C.To help the liquid behave normally.
D.To enable the water to move rapidly.
【小题4】What is the author’s attitude toward the idea of humans’ walking on water?
A.It is risky but beneficial.
B.It is interesting and worth trying.
C.It is crazy and cannot become a reality.
D.It is impractical though theoretically possible.

同类题4

Internet use appears to cause a decline in psychological well-being(安康), according to research at Carnegie Mellon University.
Even people who spent just a few hours a week on the Internet experienced more depression and loneliness than those who logged on less frequently, the two-year study showed. And it wasn’t that people who were already feeling bad spent more time on the Internet, but that using the Net actually appeared to cause the bad feeling.
Researchers are puzzling over the results, which were completely contrary to their expectations. They expected that the net would prove socially healthier than television, since the Net allows users to choose their information and to communicate with others.
The fact that Internet use reduces time available for family and friends may account for the drop in well-being, researchers suggested. Faceless, bodiless “virtual”(虚拟的)communication may be less psychologically satisfying than actual conversation, and the relationship formed through it may be shallower. Another possibility is that exposure to the wider world via the Net makes users less satisfied with their lives.
“But it’s important to remember this is not about the technology  per se; it’s about how it is used,” says psychologist Christine Riley of Intel, one of the study’s sponsors. “It really points to the need for considering social effects in terms of how you design applications and services for technology.”
【小题1】The best title for this passage would be ________.
A.Internet may Cause Depression
B.The Dark Side of Internet
C.How to Use Technology Properly
D.The Importance of Psychological Well-being
【小题2】Internet use may cause a decline in psychological well-being because ________.
A.people who were already feeling bad spend more time on the Internet
B.Internet users thought the world was wider than it really was
C.people were too eager to turn the “virtual” communication into reality
D.people have less time for actual communication with their family and friends
【小题3】What does the underlined Latin word “per se” (in Para. 5) mean?
A.probablyB.absolutely
C.oneselfD.itself
【小题4】What’s the tone of the passage?
A.Optimistic.B.Critical.
C.Objective.D.Pessimistic.

同类题5

   When we are in a bad mood or ill at ease, as long as we listen to a beautiful song, we will feel better and relaxed. A musical _____ always makes us comfortable. By listening to music, we also can understand the philosophies which _____ the music.

Music not only can change our moods, but also can _____ some kinds of diseases, such as insomnia (失眠). Music treatment has been _____ in many countries recently. It has been _____ that music can make people relaxed, more _____ and have a better sleep. Some music even can promote us to _____ a certain number of natural chemicals from our bodies. Besides, music also has a good effect on strengthening people’s memory. In a university, 60 girl students accepted a (n) _____ , It showed that the girls who received musical training in their childhoods could _____ 17% more reading materials than those who didn’t. Some experts also ______ that musicians’ left brains are bigger in size than ordinary people’s. As we know, our memory is ______ by the left brain. That might be the reason why those who receive musical training have a better memory. ______ , the patients whose speaking is damaged may recover ______ by listening to or appreciating some music.

In addition to these ______, music can also promote children’s intelligence growth and ______ people's life. In some countries, people conducted a (n) ______ experiment. They played music beside vegetables and cows. As a result, the vegetables grew faster and the cows produced more milk. Why does music have so many magical functions? ______ , music influences people in psychological and physical ways.

From a psychological angle, music can impact directly on people's moods and behavior. Music has various rhythms, and so do human beings. When the two kinds of rhythms are in ______, the former can adopt the latter’s psychological rhythms. Usually, people will ______ music’s rhythms to change their movements.

From a physical angle, music is a sound wave which has a range of frequency. The wave can have ______ on people’s every neuron, which can secrete (分泌) some chemicals that are good for our health

【小题1】
A.conditionB.educationC.contextD.training
【小题2】
A.consist ofB.lie inC.belong toD.center around
【小题3】
A.treatB.causeC.preventD.settle
【小题4】
A.forbiddenB.demandedC.reformedD.adopted
【小题5】
A.provedB.suggestedC.recognizedD.estimated
【小题6】
A.intelligentB.mercifulC.energeticD.enthusiastic
【小题7】
A.repeatB.reduceC.releaseD.reject
【小题8】
A.examinationB.surveyC.programD.invitation
【小题9】
A.rememberB.imagineC.acceptD.understand
【小题10】
A.realizedB.revealedC.predictedD.recommended
【小题11】
A.possessedB.influencedC.unitedD.controlled
【小题12】
A.HoweverB.FurthermoreC.StillD.Therefore
【小题13】
A.suddenlyB.slightlyC.graduallyD.regularly
【小题14】
A.functionsB.principlesC.secretsD.keys
【小题15】
A.broadB.extendC.expandD.stretch
【小题16】
A.interestingB.ridiculousC.practicalD.scientific
【小题17】
A.In generalB.In factC.In contrastD.By comparison
【小题18】
A.useB.workC.harmonyD.conflict
【小题19】
A.changeB.followC.recordD.adapt
【小题20】
A.pressureB.cautionC.effectD.Progress