The sound of a mosquito can mean trouble in many parts of the world. The bite of the mosquito can be deadly. The insects carry serious diseases like malaria. It is estimated that almost 630,000 people died from malaria and malaria-related causes in 2012, and most of these cases were in African countries.
In the United States, a group of California scientists is working to develop a more effective and less costly substance(物質(zhì))to protect people from mosquitoes. The researchers are investigating the sense of smell in mosquitoes. They found the insects use the same receptor(感受器)for identifying carbon dioxide in human breath as they do for the smell of our skin. Anandasankar Ray, who is leading the investigation, says scientists tested more than a million chemical compounds(化合物)until they found a substance called Ethyl pyruvate. He says Ethyl pyruvate makes the mosquitoes' receptor inactive. ”When we apply Ethyl pyruvate to a human arm and offer it to hungry mosquitoes in a cage, very few of the mosquitoes are attracted to the human arm because only a few of them are able to smell it out,” said Ray.
Genevieve Tauxe, a member of the research team, says it was not easy to find the neurons (神經(jīng)元)of nose cells that recognise both the smell of human breath and skin. "With the device used to examine mosquitoes, we are able to insert a very small electrode(電極)into the part of the mosquitoes' nose, where its smelling neurons are and where the smell is happening," said Tauxe.
Anandasankar Ray says a product based on Ethyl pyruvate may cost less to produce than DEFT,the most effective chemical treatment now in use. He says DEFT is too costly for most people who live in areas affected by malaria.
“Perhaps by finding smells that can attack other target receptors, we will be able to improve upon DEFT and finally have the next generation of insect behavior control products," said Ray.
小題1:The best title for the passage is most probably _______________________________.
A.Scientists Find New Substance to Fight Mosquitoes
B.A New Generation of DEET Has Been Developed to Kill Mosquitoes
C.Malaria一a Serious Disease Causing 630,000 Deaths
D.Ethyl Pyruvate一an Insect Behavior Control Product
小題2:According to the passage, Ethyl Pyruvate can_______________________________.
A.kill the mosquitoes' smelling neurons
B.cause the mosquitoes to lose their sense of smell
C.result in the inactiveness of the mosquitoes' receptor
D.make the mosquitoes uninterested in human breath and skin smell
小題3:Through the passage, the writer aims to_______________________________.
A.inform readers of the new development in fighting mosquitoes
B.praise the achievements made in the battle against malaria
C.introduce a cheaper product in fighting mosquitoes
D.tell the differences between Ethyl Pyruvate and DEET
小題4:This passage most probably appears in_______________________________.
A.the column of newspaper ads
B.the health column of a magazine
C.a(chǎn) textbook of medical schools
D.a(chǎn) collection of doctors' essays

小題1:A
小題2:C
小題3:A
小題4:B

試題分析: 蚊子的嗡嗡叫對于人們來說是個(gè)麻煩的問題,而它們的叮咬甚至有可能是致命的。所幸科學(xué)家們研究了一種能夠影響蚊子嗅覺的藥物,從而影響蚊子的叮人的行為。
小題1:A。文章標(biāo)題類題。通過文章最后一段we will be able to improve upon DEFT and finally have the next generation of insect behavior control products可知DEFT只是一種殺蚊藥,而文章主要講科學(xué)家研制出一種新的效果明顯花費(fèi)低的藥品。側(cè)重點(diǎn)在于新的藥品。故選A。
小題2:C。細(xì)節(jié)題。通過第二段He says Ethyl Pyruvate makes the mosquitoes' receptor inactive. 可知Ethyl Pyruvate會使蚊子的感受器遲鈍。故選C。
小題3:A。作者態(tài)度觀點(diǎn)題。文章主要介紹了科學(xué)家研究一種能夠影響蚊子嗅覺的藥物,從而影響蚊子的叮人的行為。文章中作者只是客觀介紹藥物,并沒有表明自己是贊揚(yáng)還是批評的觀點(diǎn)。故選A。
小題4:B。文章類型推測題。A:報(bào)紙新聞板塊B:雜志的健康板塊C:醫(yī)學(xué)院的教科書D:醫(yī)學(xué)散文的文集。通過理解文章大意,故選B。
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科目:高中英語 來源:不詳 題型:閱讀理解

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科目:高中英語 來源:不詳 題型:完形填空

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科目:高中英語 來源:不詳 題型:閱讀理解

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科目:高中英語 來源:不詳 題型:閱讀理解

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“Parents who ask their children where they are going, who they are going with and request a meeting with their children’s friends and the friends’ parents have already taken the first step,” says Mara Berkley, family therapist and professor at Bristol University in Rhode Island.
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A.should track him secretly B.should not ask him
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B.She meets his son’s friends herself.
C.She makes arrangements with the parents of his son’s friends.
D.She communicates with the parents of his son’s friends.
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科目:高中英語 來源:不詳 題型:閱讀理解

Can you imagine learning by playing games. To be sure, only children experienced some things differently from those with sisters and brothers. Many feel more pressure to succeed. They also tend to look only to their parents as role models in the absence of brothers and sisters.
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In the future, more and more only children will likely face similar choices. With working mothers increasing, many families are finding they simply don't have the time, money or energy to have more than one child. As only children become common, perhaps the world will realize that the Charge made against them is unjust.
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B.be responsible for bringing up her only child
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