A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.
Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.
Now the same oxygen sensors found in frog skins and in the lungs of mammals (哺乳动物) have unexpectedly been discovered in the skin of mice.
“No one had ever looked,” explained Randall Johnson, a biologist researcher.
Mice and frogs are quite distant relatives, so the fact they have these molecules (分子) in common in their skin suggests they might well be found in the skin of other mammals, such as humans.
“We have no reason to think that they are not in the skin of people too,” Johnson said.
These molecules not only detect oxygen, but help increase levels of vital red blood cells, which carry oxygen around the body. Normal mice breathing in air that is 10 percent oxygen—a dangerously low level similar to conditions at the top of Mount Everest, and about half that of air at sea level. However, mice that had the oxygen sensor HIF-1a genetically removed from their skin failed to produce this hormone (荷尔蒙) even after hours of such low oxygen.
These findings, if they hold true in humans, suggest one could raise the level of oxygen circulating inside the body. This could help treat lung diseases and disorders such as anemia (贫血症) without injecting drugs, which make up a multibillion-dollar market, Johnson said.
Athletes also often try to get more oxygen delivered to their muscles in order to improve their performance. They often do this by training at high altitudes or in low-oxygen tents. The new study suggests they might want to expose their skin as well as breathing in low-oxygen air to improve their performance. “It’s hard to say what exactly might be done, however—there’s a lot we don’t know yet,” Johnson explained.
The scientists detailed their findings in the April 18 issue of the journal Cell.
【小题1】Which of the following statements is TRUE according to the passage?

A．It has long been expected oxygen sensors exist in mice’s skin.

B．People have to surf the Internet to read detailed findings.

C．It has been proved that these findings help treat lung diseases.

D．Johnson believes that Oxygen sensors also exist in human skin.

【小题2】One of the functions of the molecules mentioned above is _______.

A． increasing level of oxygen	B．improving athletes’ performance
C．detecting oxygen	D．carrying oxygen around the body

【小题3】What is Johnson’s attitude to the application of the findings to the athletes’ training?

A． Hesitating

B．Doubting

C．Positive

D．Negative

【小题4】The best title of the passage may be _______.

A． Humans Might Sense Oxygen Through Skin

B．Frogs And Mice Are Distant Relatives

C．First Known Animal Breathes Through Skin

D．Great Findings Benefits Athletes A Lot

阅读下面对话，掌握其大意，并根据所给字母的揭示，在标有题号的横线上写出一个英语单词的完整、正确形式，使对话通顺。

W=woman   M=man

W: Hi, Phil, can you tell me how it (76) h            ?               _______

M: Sure. I was mountain climbing in New Hampshire in 1982.

Suddenly the (77)w         became really bad. There was            _______

a lot of snow and we couldn’t see anything. We got (78)l        . _______

Well, we spent four days on the mountain. The (79)t                _______

was 20 degrees below zero. We didn’t have any equipment or food.

W: So what happened? I guess (80)s           found you, right?  _______

M: Yes but we were very sick. I couldn’t move my legs because

of the cold. I spent two months in the (81)h          .                 _______

The doctors removed my legs.

W: Right. So you lost your legs, but you want to try your best to stay active.

M: That’s right. In (82)f          , I decided to make some          _______

new legs for myself. I realize that no one has to be physically

disabled. We can use modern (83)t_________  to help.                 _______

W: And you built these great new legs. Can you go

mountain (84)c          again?                                                _______

M: Yes, I can. In fact, these are better than climb shoes. The spring（弹力）

design means they are much more (85)p         .                         _______

第四部分:书面表达（共两节，满分40分）

第一节：完成句子（共10小题；每小题1.5分，满分15分）

71.With___________________（这场火扑灭了）,the firefighters left.(put)

72.Some people act____________（不管将会发生什么）.(regardless)

73.It is said that____________（警方正在调查）the case.(look)

74.Animal rights fighters demand that______________（动物应当被对待）in the same way as human beings.

75.____________（穿着）her beautiful dress, Mary went to the party, and soon became the centre of attention.( dress)

76.Half of the rivers are thought___________（污染了）in the past 20 years.(pollute)

77.—Look, Mike has fallen asleep.

—Oh, he____________（必定熬夜了）too late last night.(stay)

78.The child is____________（对看……感到厌倦）the same cartoon movies all the time.(get)

79.Newspapers and magazines___________（禁止）take out of the reading rooms of the library.(forbid)

80.All flights____________（已取消）because of the snowstorm, many passengers have no choice but to take a train.(cancel)

 

From the beginning rivers have played an important in the life of man．Man of the earliest times used the rivers as a means of travel．Today rivers still serve as a great waterway for the transport and people．
In ancient times, man settled near rivers or on river banks and built up large empires．
Water is nature’s most valuable gift to man．Man needs water to irrigate his crops, to cook and to wash．In nations all over the world, rivers mean life and wealth．They feed and clothe the nations around them．
Water is also a source of energy and power．Man build huge dams across the rivers to control the water for irrigation and get the energy needed to drive generators．The electrical power is then directed to homes, cities, factories and television stations．
Man uses water each day．In a small way rivers help to keep man in good health and provide for his amusements．Various forms of water sports keep man strong and healthy．
【小题1】Rivers have been important to man _______．

A．since they came into being	B．since the last century
C．since a few hundred years ago．	D．since the beginning of BC

【小题2】Man in old times traveled from one continent to another ______．

A．by air

B．by sea

C．by train

D．by bus

【小题3】Generators are machines that are used ______．

A．to direct electrical power	B．to control the water
C．to produce electricit	D．to build dams y

【小题4】Which of the following statements is true?

A．People get energy by building bridges across rivers．

B．In ancient times large empires grew up near dams．

C．People can be provided with amusements in small rivers．

D．Large rivers are still useful for transportation in modern times．

根据短文内容,从短文后的选项中选出能填入空白的最佳选项。选项中有两项为多余选项。 (E=AB  F= AC   G=AD)

M: Welcome back! I didn’t see you in the history class on Friday.

W:  61   . My geography class went on a field trip to look at some of the different rocks.

M: Really?  62   ! Where did you go?

W: A desert. It gets hot during the day, but it cools off very quickly at night.   63   .

M: Well, did you enjoy the trip?

W: Of course I did. Since there are so few plants growing there, it’s very easy to see different

rocks.

M:   64   . You must call me if you have the chance to go there again.

W: No problem.   65   .

A. I really want to go there

B. That sounds excellent

C. I will be your guide next time

D. It is very dry there after the sun goes down

E. I’m tired of this trip

F. I wasn’t here on Friday