15.Spring is here,the colourful flowers are seen everywhere but it is pity that many of us are not able to smell them while enjoying the colourful flowers?
Growing levels of air pollution from the factories and cars have reduced flower fragrances(芳香) by up to 90percent in the US,compared with pre-industrial levels 100years ago.
But if the trend is simply unpleasant for human noses,it may be life-dangerous for bees and butterflies.
Many insects find flowers by following the scent produced by those flowers.
The increasing pollution makes it difficult for them to find the flowers and feed on their nectar(花蜜).
Scientists have already found that flowers produce scent molecules(气味分子) that mix with polluted things,which breaks down the plants'sweet smell.
With more pollution in the air,the scent molecules don't remain powerful as long and travel shorter distances on the wind.In the mid-19th century,when pollution levels were first recorded,scent molecules would have been able to travel some 1,000to 1,200meters.Today,in the polluted air of large cities,scents may only make it some 200to 300meters.
Also,pollution from polluted air may fool the bee's"nose",making their search for flowers all the more difficult.
In a paper published recently in Scientific Reports,scientists said that the nitric oxide(NO) and nitrogen dioxide (NO2)in polluted air could change many chemicals that work together to give a flower its special smell.
This,researchers said,"could prevent honeybees from reaching their flowers and prevent the pollination(授粉) of some of the world's food crops."Or,this could put in danger agricultural harvests worldwide.
But the bees seem to have learned to get used to the changing world."In nature honeybees use their special eyes and flower smell to find out where a flower is for the first time,"the researchers said.
57.According to the article,researchers have recently found thatB.
A.reduced flower fragrances have resulted in the dying out of many bees and butterflies
B.reduced flower fragrances are connected to growing levels of air pollution
C.polluted things in the air prevent flowers from producing scent molecules
D.flowers today can't produce enough nectar because of air pollution
58.What do the underlined words"the trend"in Paragraph 3refer to (指的是)?B
A.Increasing air pollution
B.Reduce flower fragrances.
C.Human beings'worse sense of smell
D.A growing number of power plants and cars
59.The scent molecules a plant produces are mainly toC.
A.help flowers to produce nectar
B.prevent insects from eating the plant
C.draw attention from bees and butterflies
D.clear up polluted things in the air
60.We can infer(推断) from the article thatB.
A.future food crops won't depend on bees to complete their pollination
B.some bees have successfully get over the challenge of reduced flowers fragrance
C.bees have great advantages in their senses compared to humans.
D.world food crop production is likely to fall greatly in the near future.
分析 文章大意:主要描述了随着工业的发展,污染相当严重,使靠气味寻找花采蜜的蜜蜂很困难找到花,但一份研究表明,蜜蜂似乎已经适应了这个变化,同样找到花采蜜.
解答 57题答案:B 考查细节理解题,根据文中的第一段Spring is here,the colourful flowers are seen everywhere but it is pity that many of us are not able to smell them while enjoying the colourful flowers?可知日益严重的污染使我们闻不到花香,故答案是B.
58题答案:B 考查词汇题,根据文中的第二段Growing levels of air pollution from the factories and cars have reduced flower fragrances by up to 90percent in the US,compared with pre-industrial levels 100years ago.从100年前的工业水平来看,工厂和汽车的空气污染水平在美国已经减少了多达百分之90的花香.可知后面说这种趋势指的是花香的减少,故答案是B.
59题答案:C 考查细节理解题,根据文中的倒数第二段This,researchers said,"could prevent honeybees from reaching their flowers and prevent the pollination of some of the world's food crops."Or,this could put in danger agricultural harvests worldwide.可知 花的气味是吸引蜜蜂和蝴蝶授粉,故答案是C.
60题答案:B 考查细节理解题,根据文中的最后一段But the bees seem to have learned to get used to the changing world."In nature honeybees use their special eyes and flower smell to find out where a flower is for the first time,"the researchers said.可知但蜜蜂似乎已经学会了适应变化的世界,"在自然界中,蜜蜂第一次用它们特殊的眼睛和花的气味来发现花,故答案是B.
点评 本文是一篇日常生活类阅读,题目涉及多道细节理解题,做题时结合原文和题目有针对 性找出相关语句进行仔细分析,结合选项选出正确答案.推理判断也是要在抓住关键句子的基础上合理的分析才能得出正确的答案.