20.Long-time exposure (暴露) to air pollution can lead to physical changes in the brain and cause trouble in learning and memory,and even anxiety.This is suggested by the results of new research on mice.
While other studies have shown the harmful effects of polluted air in the lungs and heart,this is the first to show the negative effect on the brain.
The team of Laura Fonken,Randy Nelson,from the Ohio State University,the USA,has spread to the brain a previous line of research which found that fine particulate(微粒) matter floating in the air mainly because of air pollution caused by humans,causes swelling in much of the body,and may be related to high blood pressure problems,and some other diseases.
In the research Fonken and his colleagues exposed mice to polluted air for six hours each day,five days a week,over a period of 10months,almost half the average life length of mice.
Polluted air contains fine particles created by cars,factories and natural dust.Fine particles of this kind are tiny,about 2.5micrometers in diameter(直径),or about one-thirtieth the width of a human hair.These particles can go deep into lungs and other organs.
The concentration of this particulate material to which they exposed mice is equal to the concentration at which people can be exposed in some polluted urban areas.
After a period of 10months,the researchers got the animals to have a series of behavioral tests.Both the behavior of mice and the results of neurological (神经的) tests done to them show that those within the polluted air had more problems in learning and memory,and higher levels of anxiety.
The results suggest that long-time exposure to polluted air can have measurable negative effects on the human brain and can cause a variety of mental health problems.This could have important consequences for those living and working in polluted urban areas.
28.The results of new research on mice first suggest that polluted air mainly does harm toC
A.normal organs
B.lungs and heart
C.mental health
D.blood pressure
29.What harmful effect of polluted air is mentioned in other studies?C
A.The harmful effect on learning.
B.The harmful effect on all the organs.
C.The harmful effect on lungs and heart.
D.The harmful effect on improving memory.
30.Which of the following is the best title for the passage?D
A.Long-time Exposure to Air Pollution
B.Evidence and Concern of Air Pollution
C.Measurable Effect on Human Brain
D.Mental Problems Caused by Air Pollution.
分析 文章主要讲述了通过一个新的针对空气污染物的实验得出的结论-长期暴露在被污染的空气中有可能引起心理健康方面的问题.
解答 28-30 CCD
28 C 细节题.由最后一段第一句"The results suggest that long-time exposure to polluted air can have measurable negative effects on the human brain and can cause a variety of mental health problems."可知,这项新的研究表明,污染的空气主要对心理健康有危害.故正确答案为C.
29 C 细节题.由第二段第一句"While other studies have shown the harmful effects of polluted air in the lungs and heart…"可知,其他研究表明,污染的空气对肺和心脏有危害.故正确答案为C.
30 D 主旨题.主旨句为最后一段第一句"The results suggest that long-time exposure to polluted air can have measurable negative effects on the human brain and can cause a variety of mental health problems."文章主要讲述了通过一个新的针对空气污染物的实验得出的结论-长期暴露在被污染的空气中有可能引起心理健康方面的问题.只有D项最全面,阐释了原因和结果.故正确答案为D.
点评 做阅读理解时要快速的浏览全文,把握文章主旨大意,带着问题回到原文,寻找细节或概括相应的答案,最后要理清作者写作思路.