Question

    When we exercise hard, we burn fat. But have you ever wondered where exactly the fat goes?

Some doctors think that fat is changed into heat and released in the air. Others think the body burns it. Some even joke that the fat fairy comes and takes it. That is why you always weigh less in the morning.

Now a new study from the University of New South Wales in Australia reveals the mystery. “the correct answer is that most of the mass is breathed out as carbon dioxide(二氧化碳). It goes into thin air,” says the study’s lead author, Ruben Meerman, to Science Daily. Scientists followed the atoms(原子) in 10 kilograms of fat as they are lost. They found that 8.4 of those kilograms are breathed out as carbon dioxide through the lungs. The rest of the weight —1.6 kilograms— becomes water that leaves the body in the form of fluids(液体) such as urine(尿), sweat, breath and tears. “None of this is obvious to people because we can’t see the carbon dioxide gas we breathe out,” said Meerman.

Does that mean you can lose more weight by breathing more? It is not as easy as you think. Breathing more than the body’s metabolic rate(新陈代谢) can make you uncomfortable. You may feel dizzy and become unconscious(无意识的), according the study. So how to lose weight healthily? The key is to eat less and move more. You many have heard this many times.

During a day, a 70kg person breathes out about 200g of carbon dioxide. So if the same person wants to lose weight, he or she can do some light exercise, for example, jogging. This can help lose 240g of carbon dioxide.

1.According to the new study, where does our fat go when we exercise a lot?

A.It is changed into heat and given off in the air. B.The body burns it.

C.The fat fairy comes and takes it. D.Most of it is breathed out as carbon dioxide.

2.What will happen to people if they breathe more than the body’s metabolic rate?

A.They will put on more weight. B.They will feel comfortable.

C.They may become unconscious. D.They may not lose weight at all.

3.Which of the following is a better way to lose weight?

A.Sitting still and breathing more. B.Sleeping a lot and breathing a lot.

C.Eating less and exercising more. D.Eating more and doing some light exercise.

4.Which is true according to the study from University of New South Wales?

A.The fat is changed into heat and released in the air.

B.Most of the kilograms of fat as they are lost are breathed out as carbon dioxide.

C.People can see the carbon dioxide gas we breathe out.

D.If we breathe more than the body’s metabolic rate, we will feel good.

5.During a week , how much carbon dioxide does a 70kg person breathes out?

A.240g B.200g C.1400g D.1680g

Answer

1.D

2.C

3.C

4.B

5.C

【解析】

本文属于说明文阅读。作者通过这篇文章向我们介绍了当我们锻炼时脂肪的去向，它们会通过我们的呼吸转变成二氧化碳，而最好的减肥方式就是少吃多锻炼。

1.细节理解题。根据“the correct answer is that most of the mass is breathed out as carbon dioxide(二氧化碳). It goes into thin air.” says the study’s lead author, Ruben Meerman, to Science Daily.”可知，当我们锻炼的时候大部分的脂肪通过我们的呼吸转变成了二氧化碳。故选D。

2.细节理解题。根据“Breathing more than the body’s metabolic rate(新陈代谢) can make you uncomfortable. You may feel dizzy and become unconscious(无意识的), according the study.”可知，呼吸超过身体代谢率会让你感到不舒服。研究表明，你可能会感到头晕，失去知觉。故选C。

3.细节理解题。根据最后一段“So how to lose weight healthily? The key is to eat less and move more.”可知最好的减肥方式就是少吃多锻炼。故选C。

4.细节理解题。根据“the correct answer is that most of the mass is breathed out as carbon dioxide(二氧化碳).”正确的答案是，大部分物质是以二氧化碳的形式呼出的。可知，减掉的大部分脂肪都是以二氧化碳的形式排出的。因此B正确；而“Some doctors think that fat is changed into heat and released in the air.脂肪转化为热量并释放到空气中。”的说法就是错误的。因为当我们锻炼的时候大部分的脂肪通过我们的呼吸转变成了二氧化碳。因此A不对；根据“None of this is obvious to people because we can’t see the carbon dioxide gas we breathe out,” said Meerman.”米尔曼说：“这些对人们来说都不明显，因为我们看不到呼出的二氧化碳气体。”。可知C不对；根据“Breathing more than the body’s metabolic rate(新陈代谢) can make you uncomfortable.”呼吸超过身体代谢率会让你感到不舒服。可知D不对。故正确的是B。

5.细节理解题。根据“During a day, a 70kg person breathes out about 200g of carbon dioxide.”一天中，一个70公斤重的人呼出约200克二氧化碳。可知，一周内，一个70公斤重的人呼吸出1400g（200克x7=1400克）二氧化碳？ 故选C。