题目内容

Nature is full of color, from rainbows and roses to butterfly wings and peacock tails. Even the fruits and vegetables you eat have different colors: blue blueberries, red strawberries, green broccoli, and orange carrots.

Plant and animals often use color to attract attention. The substances responsible for these colors belong to a class of chemical called antioxidants(抗氧化物). Plants make antioxidant to protect themselves from the sun’s ultraviolet(UV)(紫外线)light.

Ultraviolet light causes chemicals called free radicals(自由基)to form within plant cells. They can destroy parts of plant. Free radicals also have damaging effects on human beings. Some of these effects like wrinkled skin can be seen. The damage is caused by the free radicals attacking cells in our bodies. Certain cancers and heart disease are linked to free radicals.

Our bodies have natural defences for fighting off free radicals. While we are young, our defences are pretty strong. However, they get weaker as we get older. The body’s built-in defences can only go so far without extra help.

The key to fighting free radicals with fruits and vegetables is to mix and match colors. It’s like sunscreen(防晒霜)for the inside of your body. Go for a range of very bright colors. Colorful foods contain hundreds of healthy chemicals not found anywhere else.

Research into how chemicals in blueberries affect the brain’s function in rats suggests that these chemicals may help our own brains work more efficiently.

Don’t just blame the sun. Ultraviolet light isn’t the only source of free radicals. If you breathe polluted air such as smog, automobile exhaust(废气), or wasted gas from a factory, you take in chemicals that also cause such damage. And, the body itself produces free radicals as it processes food.

1.Which of the following not true?

A.Antioxidants are responsible for plant colors

B.Plants use color to attract attention

C.Antioxidants can protect plants from UV light

D.Antioxidants help free radicals to attack plants

2.In which order do the following facts occur?

a Wrinkled skin can be seen

b UV light causes free radicals to form

c Free radicals damage cells in our bodies

d The sun gives out UV light

A.a,b,c,d                                B.d,b,c,a

C.c,a,d,b                                D.d,b,a,c

3.We need extra help for fighting off free radicals from fruits and vegetables because ____.

A.our bodies’ defences are not natural

B.we are too young to defend ourselves

C.our defences get weaker as we get older

D.our bodies’ built-in defences can only go away

4.Which of the following can not cause free radicals to form?

A.Colorful food                          B.UV light from the sun

C.Polluted air                            D.The body itself

 

【答案】

1.D

2.B

3.C

4.A

【解析】

试题分析:这篇文章讲述了太阳的紫外线、烟雾、汽车的排气、工厂的废气等都可造成自由基的生成,自由基会破坏人体细胞,各种颜色的食物是帮助我们抗自由基的有效方法。

1.根据Plant and animals often use color to attract attention. The substances responsible for these colors belong to a class of chemical called antioxidants(抗氧化物). Plants make antioxidant to protect themselves from the sun’s ultraviolet(UV)(紫外线)light.排除A、B和C,故选D。

2.事情发生的先后顺序是:先是太阳释放出紫外线,然后紫外线造成自由基的生成,接着自由基破坏我们身体的细胞,最后皮肤起皱纹,故选B。

3.根据However, they get weaker as we get older. The body’s built-in defences can only go so far without extra help.所以答案为C。

4.各种颜色的食物是帮助我们抗自由基的,因此选A。

考点:教育类短文阅读理解

点评:要想答好题目,重在理解全文意思。这篇文章比较难,先看问题,再带着问题读短文,找出各段落的主旨句,理解全文内容,总结全文中心,然后再回到问题上来,很容易选出正确答案。

 

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Electric ears are dirty.In fact, not only are they dirty, they might even be more dirty than their gasoline-powered cousins.

    People in California love to talk about "zero-emissions vehicles", but people in California seem to be clueless about where electricity comes from. Power plants mostly use fire to make it. Aside from the new folks who have their roofs covered with solar cells, we get our electricity from generators. Generators are fueled by something---usually coal, oil,but also by heat generated in nuclear power plants. There are a few wind farms and geothermal plants as well, but by far we get electricity mainly by burning something.

    In other words, those "zero-emissions" cars are likely coal-burning cars. It's just because the coal is burned somewhere else that it looks clean. It is not. It's as if the California Greens are. covering their eyes---"If I can't see it, it's not happening." Gasoline is an incredibly efficient way to power a vehicle; a gallon of gas has a lot of energy in it.But when you take that gas (or another fuel) and first use it to make electricity, you waste a nice part of that energy, mostly in the form of wasted heat---at the generator, through the transmission lines, etc.

    A gallon of gas may propel your car 25 miles. But the electricity you get from that gallon of gas won't get you nearly as far---so electric cars bum more fuel than gas-powered ones. If our electricity came mostly from nukes; or geothermal,or hydro, or solar, or wind,then an electric car truly would be clean. But for political, technical,and economic reasons,we don't use much of those energy sources.

    In addition,electric cars' batteries which are poisonous for a long time will eventually end up in a landfill.And finally, When cars are the polluters, the pollution is spread across all the roads. When it's a power plant, though, all the junk is in one place. Nature is very good at cleaning up when things are too concentrated, but it takes a lot longer when all the garbage is in one spot.

What does "clueless" mean in paragraph 2?

    A. People are seeing the California Greens everywhere.

    B. People in California love to talk about zero-emissions vehicles.

    C. People in California love to have their roofs covered with solar cells.

D. People there have no idea that so far electricity mainly comes from burning

   coal, oil,etc.

What is the main idea of the passage?

    A. Electric cars are not clean at all

    B. Electric cars are better than gasoline-powered ones.

    C. People cast doubts on electric cars' batteries.

    D. Gasoline is an efficient way to powera vehicle.

The electricity we get from a gallon of gas may make our ear run         

    A. not less than 25 miles            B. more than 25 miles

    C. no more than 25 miles             D. not more than 25 miles

According to the passage, electric cars                  .

    A. do not burn fuel and more environmentally-friendly

B. are toxic because it is difficult for nature to clean it up when their

   batteries are buried in one spot.

    C. are very good at cleaning up when things are not too concentrated

    D. are poisonous for a long time and will eventually end up in a landfill

It can be inferred from the passage that                 

    A. being green is good and should be encouraged in communication

B. electric cars are not clean in that we get electricity mainly by burning

   something

    C. zero-emissions vehicles should be chosen to protect our environment

D. electric cars are now the dominant vehicle compared with gasoline-powered

   cousins


(D)
People living in the country enjoy several advantages that people living in the city cannot enjoy.
They are in close contact with nature. They make friends with trees and stones. They breathe fresh air. They fight with strong winds. They listen to the song of birds.
This contact with nature is good for health. There are many diseases that are common in the city, but are not to be found in the country, For example, near-sightedness is almost unknown to country people.
Because of the absence of cars, one can walk more freely in the country than in the city, There are no rules of the road nor traffic signs to obey.
People living in the country can easily get fresh vegetables, fresh fruit and fresh milk, Are they get them at lower prices than in the city.
Country life is economical in other ways, too. There are practically no temptations to waste money.
Country people are mostly honest. They say what they mean, and make and keep promises with sincerity. They do not put on air (摆架子). They do not pretend to have those ridiculous manners which are necessary in what we call polite society.
67. What CAN’T country people often enjoy?
A. Musical concerts.          B. Fresh air.   
C. Song of birds.             D. Close contact with nature.
68. What is probably more expensive in the country than in the city?
A. Vegetables.          B. Beer.          C. Milk.           D. Fruit.
69. What is NOT true of country life?
A. The traffic accident rate is very high in the country.
B. Living in the country saves one a lot of money.
C. Country people enjoy better health than the city people.
D. Country people are honest.
70. Which of the following statements is true according to the passage?
A. People living in the country enjoy no advantages.
B. People living in the city are in close contact with nature.
C. People living in the country suffer from more diseases than those living in
the city.
D. The prices of farm products are lower in the country than in the city.
71. Which of the following would be the best title for the passage?
A. The Disadvantages of Living in the Country.
B. The Expenses of Living in the Country.
C. Country Life.
D. Healthy Country People.

 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。

People living in the country enjoy several advantages that people living in the city cannot enjoy.

    ___1.______They make friends with trees and stones. They breathe fresh air. They fight with strong winds. __2.______.

    This contact with nature is good for health. There are many diseases that are common in the city, but are not to be found in the country, For example, near-sightedness is almost unknown to country people.

    Because of the absence of cars, one can walk more freely in the country than in the city, ___3._____

    People living in the country can easily get fresh vegetables, fresh fruit and fresh milk, and they get them at lower prices than in the city.

    ____4.____There are practically no temptations to waste money.

    _____5.____ They say what they mean, and make and keep promises with sincerity (诚意). They do not put on air (摆架子). They do not pretend to have those ridiculous manners which are necessary in what we call polite society.

 

A. They listen to the song of birds.

B. Country people are mostly honest.

C. They are in close contact with nature.

D. Country people are far from town life.

E. Country life is economical (节俭的) in other ways, too.

F. Country life provides much more enjoyment.

G. There are no rules of the road nor traffic signs to obey.

 

(答题处)  71.        72.       73.       74.       75.        

 

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