8.No offence to you,but scientists have found that mosquitoes may find your feet as attractive as Limburger cheese.If that's you,don't feel embarrassed-it doesn't mean you're not washing them enough.Mosquitoes are simply attracted by certain DNA.
A UK research team recently investigated the genetic role in mosquito attraction by testing the bite appeal of 18twin sisters and 18 non-twin sisters.In a series of tests,20hungry mosquitoes were released into the end of a Y-shaped tube and allowed to choose left or right.Down either path was one sister's hand,releasing its delicious natural odors but protected from bites behind a net screen.After testing all 36pairs,scientists found that the twin pairs had consistently more similar attraction scores than the non-twin ones did-specifically,67 percent of a person's insect appeal had to do with her genes.
So what's the deal:does DNA smell?Thankfully,no.But specific DNA does attract unique species of microbacteria to your body-and those are what mosquitoes just can't resist.
Each of us,right now,is covered with about 100 trillion microbes(微生物),outnumbering our human DNA ten to one.Maybe weirder still:scientists believe we share only a fraction of these microbial species with one another,making our'microbiome'-the world of bacteria living in and on us-unique,just like our fingerprints.In addition to producing many of the vitamins and chemicals in our blood,our microbiome is thought to be responsible for most of our distinct odors as well.
Different mosquitoes prefer different smells from different parts of the body-that's why Anopheles gambiae (known for spreading malaria) prefers biting hands and feet,while others go right for the armpits or groin.And those smells come from chemicals produced by our microbiomes.So the next time a group of hungry mosquitoes swarms your cousin but leaves you bite-free,thank your DNA for the world of microscopic creatures on your skin that produce just the right smell to keep the bloodsuckers away.
32.The research conducted by the UK team suggested thatD.
A.more mosquitoes chose the twin pairs
B.more mosquitoes chose the non-twin pairs
C.Non-twin pairs had more similar attraction than twin pairs
D.most insect appeal had to do with a person's DNA
33.What does the word"those"in Paragraph 3 refer to?B
A.a specific DNA
B.the microbateria
C.the smell of body
D.the attractive blood
34.From Paragraph 4,we can learn thatB.
A.we are part of our microbiome.
B.our microbiome contributes to our distinct odors
C.our microbiome will decide our fingerprints in some way
D.our microbiome produces vitamins and nutrients in our blood
35.What does the passage mainly talk about?D
A.We are attractive to the mosquitoes.
B.Different mosquitoes prefer different smells.
C.DNA that attracts mosquitoes makes us unique.
D.Mosquitoes are simply attracted by certain DNA.
分析 短文主要讲了科学家通过研究表明蚊子喜欢咬具有某一些DNA的人,并且不同的蚊子也喜欢咬人身体不同的部位.
解答 32.D,细节理解题,根据句子67 percent of a person's insect appeal had to do with her genes.可知,吸引大多数昆虫的是人的DNA,故答案为D.
33.B,单词指代题,分析整个句子,代词those指代的是前文提到的unique species of microbacteria,故答案为"微生物",选B.
34.B,细节理解题,根据第四段句子our microbiome is thought to be responsible for most of our distinct odors as well可知,我们的微生物造成我们不同的气味,故答案为B.
35.D,主旨大意题,短文主要讲了科学家通过研究表明蚊子喜欢咬具有某一些DNA的人,并且不同的蚊子也喜欢咬人身体不同的部位,故答案为D.
点评 解答任务型阅读理解题,首先对原文材料迅速浏览,掌握全文的主旨大意.因为阅读理解题一般没有标题,所以,速读全文,抓住中心主旨很有必要,在速读的过程中,应尽可能多地捕获信息材料.其次,细读题材,各个击破.掌握全文的大意之后,细细阅读每篇材料后的问题,弄清每题要求后,带着问题,再回到原文中去寻找、捕获有关信息.最后,要善于抓住每段的主题句,阅读时,要有较强的针对性.对于捕获到的信息,要做认真分析,仔细推敲,理解透彻,只有这样,针对题目要求,才能做到稳、准.