Vitamin D helps bones and muscles grow strong and healthy．Low levels of vitamin D can lead to diseases such as rickets(軟骨病), mainly found in children．The thinning of bone is a common problem as people, especially women, get older．

But more and more research is suggesting that vitamin D might also help prevent many diseases．The easiest way to get vitamin D is from sunlight．The sun’s ultraviolet(紫外線的)rays react with skin cells to produce vitamin D．But many people worry about getting skin cancer and skin damage from the sun．As a result they stay out of the sun．Also, darker-skinned people produce less vitamin D than lighter-skinned people．The amount also de-creases in older people and those living in northern areas that get less sunlight．

Not many foods naturally contain vitamin D．Foods high in this vitamin include oily fish and fish liver oils．Farmed fish have only about one-fourth as much vitamin D as wild fish．Small amounts of vitamin D are found in beef liver, cheese and egg yolks．But most of the vitamin D in the American diet comes from foods such as milk．

Research in the last several years has shown that low levels of vitamin D may increase the risk of heart attacks in men and deaths from some cancers．More doctors are now having their patients tested for their vitamin D levels．But as research continues, some experts worry that if people take too much vitamin D, it might act as a poison, Also, skin doctors warn people be careful with sun exposures because of the risk of skin cancer．

1.The first paragraph is mainly about     ．

       A．the muscle diseases                        B．the sources of vitamins

       C．the importance of health                    D．the functions of vitamin D

2.Which of the following people produce the least amount of vitamin D?

       A．Elderly darker-skinned people．

       B．Young lighter-skinned people．

       C．Elderly lighter-skinned people．

       D．Young darker-skinned people．

3.People can get the most vitamin D from     ．

       A．beef liver           B．cheese               C．wild fish           D．farmed fish

4.What can we infer from the text?

       A．Being exposed to sunlight is the safest way to get vitamin D

       B．Lack of vitamin D can make people age quickly

       C．Proper vitamin D levels people need are still not determined now．

D．The vitamin D level is higher in men than in women．

 

【答案】

1.D

2.A

3.C

4.C

 

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科目：高中英語 來源：2010—2011學(xué)年度福建省廈門第一中學(xué)高一下學(xué)期期中考試英語卷 題型：閱讀理解

A healthy amount of sunshine may be the secret to staying young. British scientists have discovered.
Vitamin D is produced naturally by the skin in response to(對…的反應(yīng)) sunlight and may help to slow the ageing process and protect against heart disease, according to the study.
Researchers from King’s College London studied 2,160 women aged between 18 and 79, looking at their telomeres--- a biological marker of ageing found in DNA. As people get older, their telomeres get shorter and they become more susceptible(易受傷害的) to certain illnesses.
But the study found women with high levels of vitamin D had comparatively longer telomeres--- a sign of being biologically younger and healthier.
The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.
Lead researcher Dr Brent Richards said, “These results are exciting because they show for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D.” This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer.”
Professor Tim Spector, a co-author of the report, added, “Although it might sound absurd
(荒唐的), it’s possible that the same sunshine which may increase our risk of skin cancer may also have a healthy effect on the general ageing process.”
Vitamin D made by the action of sunlight on the skin accounts for 90 percent of the body’s supply, but lower levels can also be got through food such as fish, eggs and breakfast cereals(粥).
Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.
【小題1】 A certain amount of sunshine helps people stay young because _____.

A．people feel happy and energetic in the sun
B．sunshine protects people against heart disease
C．vitamin D makes one’s skin look young and healthy
D．vitamin D may help to slow the ageing process
【小題2】From Brent Richards, we know that _____.
A．sunlight causes skin cancer to people with high level of vitamin D
B．the study generally has a healthy effect on the general ageing process
C．vitamin D can only be got from fish, eggs and breakfast cereals
D．the higher levels of vitamin D people have, the more slowly people may age
【小題3】What can we infer from the passage?
A. Telomeres are important signs of ageing of the DNA.
B. Sunlight can be dangerous as it causes skin cancer.
C. Sunlight does a great deal of good to our health.
D. Vitamin D can also be gained from food.
【小題4】 What is the best title of the passage?
A．Secret of Staying Young
B．Vitamin D Helps Slow Ageing
C．Sunlight and Vitamin D
D．Sunlight and Health

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    Vitamin D is produced naturally by the skin in response to(對…的反應(yīng)) sunlight and may help to slow the ageing process and protect against heart disease, according to the study.

    Researchers from King’s College London studied 2,160 women aged between 18 and 79, looking at their telomeres--- a biological marker of ageing found in DNA. As people get older, their telomeres get shorter and they become more susceptible(易受傷害的) to certain illnesses.

    But the study found women with high levels of vitamin D had comparatively longer telomeres--- a sign of being biologically younger and healthier.

    The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.

    Lead researcher Dr Brent Richards said, “These results are exciting because they show for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D.” This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer.”

Professor Tim Spector, a co-author of the report, added, “Although it might sound absurd

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    Vitamin D made by the action of sunlight on the skin accounts for 90 percent of the body’s supply, but lower levels can also be got through food such as fish, eggs and breakfast cereals(粥).

    Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.

1. A certain amount of sunshine helps people stay young because _____.

A. people feel happy and energetic in the sun          

B. sunshine protects people against heart disease

C. vitamin D makes one’s skin look young and healthy 

D. vitamin D may help to slow the ageing process

2.From Brent Richards, we know that _____.

    A. sunlight causes skin cancer to people with high level of vitamin D

    B. the study generally has a healthy effect on the general ageing process

    C. vitamin D can only be got from fish, eggs and breakfast cereals

    D. the higher levels of vitamin D people have, the more slowly people may age

3.What can we infer from the passage?

    A. Telomeres are important signs of ageing of the DNA.

    B. Sunlight can be dangerous as it causes skin cancer.

    C. Sunlight does a great deal of good to our health.

    D. Vitamin D can also be gained from food.

4. What is the best title of the passage?   

A. Secret of Staying Young                  B. Vitamin D Helps Slow Ageing

C. Sunlight and Vitamin D                   D. Sunlight and Health

 

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  1. 1.

    What’s the aim of the study by the Australian research team ?

    1. A.
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    2. B.
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    3. C.
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    4. D.
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    1. A.
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    2. B.
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    3. C.
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  3. 3.

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    1. A.
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    2. B.
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    3. C.
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    1. A.
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    2. B.
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    3. C.
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