B
Motherhood may make women smarter and may help prevent dementia (痴呆) in old age by bathing the brain in protective hormones (荷尔蒙) ，U.S.researchers reported on Thursday.
Tests on rats show that those who raise two or more litters of pups do considerably better in tests of memory and skills than rats who have no baby，and their brains show changes that suggest they may be protected against diseases such as Alzheimer’s (早老性痴呆症).University of Richmond psychology professor Craig Kinsley believes his findings will translate into humans.
“Our research shows that the hormones of pregnancy (怀孕) are protecting the brain，including estrogen (雌激素)，which we know has many neuroprotective (保护神经的) effects，” Kinsley said.
“It’s rats’ data but humans are mammals just like these animals are mammals，” he added in a telephone interview.“They go through pregnancy and hormonal changes.”Kinsley said he hoped public health officials and researchers will look to see if having had children protects a woman from Alzheimer’s and other forms of agerelated brain decline.
“When people think about pregnancy，they think about what happens to babies and the mother from the neck down，” said Kinsley，who presented his findings to the annual meeting of the Society of Neuroscience in Orlando，Florida.
“They do not realize that hormones are washing on the brain.If you look at female animals that have never gone through pregnancy，they act differently toward young.But if she goes through pregnancy，she will sacrifice her life for her infant—that is a great change in her behavior that shows in genetic alterations to the brain.”
31.How do scientists know “Motherhood may make women smarter”?
A.Some researchers have told them.
B.Many women say so.
C.They know it by experimenting on rats.
D.They know it through their own experience.
32.What does the phrase “litters of pups” mean in the second paragraph?
A.Baby rats. B.Animals.
C.Old rats. D.Grownup rats.
33.What can protect the brain of a woman according to the passage?
A.Estrogen.
B.The hormones of pregnancy.
C.More exercise.
D.Taking care of children.
34.“It’s rats’ data but humans are mammals just like these animals are mammals.” What does the sentence suggest?
A.The experiments on the rats have nothing to do with humans.
B.The experiments on the rats are very important for animals.
C.The experiments on the rats are much the same on humans.
D.The experiments on the rats are much the same on other animals.
35.Which title is the best for this passage?
A.Do You Want to Be Smarter
B.Motherhood Makes Women Smarter
C.Mysterious Hormones
D.An Important Study
C
By analyzing the DNA of the world’s oldest people，Boston University scientists said they have discovered a genetic signature(特征)of longevity.They expect soon to offer a test that could let people learn whether they can live to a very old age.
The researchers said they had no plans to patent the technique or profit from it.Instead，they expect to make a free test available on the Internet later this month to promote longevity research.
The test might show something that people wouldn’t like to know，the BU scientists warned.Genetic testing often reveals attractive but incomplete information，and it is sometimes difficult to know how to respond.People with genes for extreme longevity could face a series of difficult decisions about their careers，retirement savings，insurance coverage，medical treatments and marriages in old age.
Scientists have long sought to crack the genetic code of healthy aging.On average，people in developed countries can expect to live between 80 and 85 years，largely as a result of improvements in diet and public health.But the oldest of the old—the “wellderly”—live two to three decades longer，often free of mental and physical diseases.
The free test will be available through a public website maintained by the New England Centenarian Study.But to take the test，people will have to provide their own complete genome—which currently can cost thousands of dollars from genesequencing companies.
36.What’s the best title of the text?
A.New Discovery of Long Life
B.New Functions of DNA on Long Life
C.Scientists Invented Genes For Longevity
D.The Discovery of the Genetic Code of Healthy Aging
37.The scientists started the program to ________.
A.make more money from it
B.do research on long life
C.become known all over the world
D.find out the function of genes
38.People who live longer in developed countries ________.
A.do not work very hard
B.do much exercise every day
C.have a balanced diet
D.never need to take any medicine
39.If you hope to take the test，you ________.
A.must be healthy enough
B.will spend a lot of money
C.will be charged by the website
D.have to take a series of examinations
40.According to the text people living extremely long
________.
A.will meet with many social problems
B.must save enough money for future use
C.will usually suffer from hunger
D.will have to face many natural disasters
D
“I got married at 16，”says the smiling Mona Lisa，made famous in Leonardo Da Vinci’s famous painting.She breaks her silence to wave to the audience and answers their questions.
Thanks to 3D technology，holographic images(全息影像)and voice recognition technologies，Mona Lisa can speak and move.It is the first time the advanced technologies have been fused together in one exhibition，which gives audiences the opportunity to experience the wonders of advanced technology.
Threedimensional，or 3D，technology creates visual illusions(错觉)and enables people to see images in the round that are actually only twodimensional.
Although 3D technology is a difficult scientific concept，it is already being widely used in people’s daily lives.With the development of new threedimensional digital technologies，it has been changing people’s ways of communicating and working.
Digital cameras that record in 3D have been brought to market.
Manufacturers have also launched 3D digital photo frames，which can broadcast 3D photos.Processing software allows flat photos in the frame to achieve 3D visual effects that can be seen by users without wearing special glasses.
After nine years of research，China took the lead to establish a 3D Internet marketing platform.Internet users can go shopping in a 3D environment just like in the real world by selecting goods，checking reviews and trying out recommended goods.
Web 3D technology will be used in more fields such as automobiles and travel.In traveling，tourists can enjoy scenic spots，monuments and sites.They also can take to guides and other tourists，who are represented as 3D virtual figures.
In Suzhou，the first online 3D police station in the world has been established.It has eight functions including various online businesses，public services，warning tips and communication between the police and the public.
41.Why can Mona Lisa speak and move?
A.Because it is a robot.
B.Because it can really speak and move.
C.Because the original painting is threedimensional.
D.Because 3D creates visual illusions.
42.The underlined word“fused”in Paragraph 2 can be replaced by “______”.
A.combined B.focused
C.applied D.developed
43.3D technology is already being used in people’s lives in ______.
A.shopping B.work
C.travel D.communication
44.How can we appreciate 3D photos?
A.By taking photos with 3D cameras.
B.By wearing special glasses.
C.By putting photos into 3D digital photo frames.
D.By installing a software into the photos.
45.We can learn from the last two paragraphs that ______.
A.in 3D travelling，we can only talk with the guide
B.3D travelling is no different from a traditional one
C.the 3D police station will replace the one in real life
D.the 3D police station is of great help
