Motherhood may make women smarter and may help prevent dementia(癡呆) in old age by bathing the brain in protective hormones(荷爾蒙) , 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 babies, and their brains show changes that suggest they may beprotected against diseases such as Alzheimer’s(早老癡呆癥). University of Richmond psychology professor Craig Kinsley believes his findings will translate into humans.
“Our research shows that the hormones of pregnancy(懷孕) are protecting the brain, including estrogen(雌激素),which we know has many neuroprotective (保護(hù)神經(jīng)的) effects,” Kinsley said. “It’s rat 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 age-related 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 who 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 showed in genetic alterations(改變) to the brain.”
【小題1】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.
【小題2】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.
【小題3】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


【小題1】C
【小題2】B
【小題3】B

解析試題分析：科學(xué)家通過對老鼠的研究發(fā)現(xiàn)，要照顧幼仔的母鼠比沒有幼仔照顧的老鼠在記憶力和技能方面表現(xiàn)更好，他們大腦的變化表明他們可能不會(huì)患早老癡呆癥，科學(xué)家們由此得出的結(jié)論是女性荷爾蒙能夠預(yù)防老年癡呆。
【小題1】C細(xì)節(jié)理解題。文章開頭提出研究結(jié)果，即 Motherhood may make women smarter and may help prevent dementia(癡呆) in old age by bathing the brain in protective hormones ,然后講述了Tests on rats show that。。。，由此可知科學(xué)家是通過在老鼠身上做實(shí)驗(yàn)得出這樣的結(jié)論，所以 B選項(xiàng)正確。
【小題2】B細(xì)節(jié)理解題。根據(jù)文中Our research shows that the hormones of pregnancy are protecting the brain, including estrogen可知B為正確選項(xiàng)。
【小題3】B主旨大意題。本篇文章是科學(xué)報(bào)道，特點(diǎn)是開頭提出中心，在本文中作者開頭提出Motherhood may make women smarter and may help prevent dementia in old age by bathing the brain in protective hormones , U.S. researchers reported on Thursday.然后圍繞這一實(shí)驗(yàn)結(jié)果進(jìn)行詳細(xì)的敘述，由此可知最佳答案為B。
考點(diǎn)：考查科學(xué)知識(shí)類短文閱讀。

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科目：高中英語 來源： 題型：閱讀理解

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【小題1】The main point of the passage is ______.

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科目：高中英語 來源： 題型：閱讀理解



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Bruce Rothschild of the University of Kansas knew all this when he began a study of ichthyosaur bones to find out how widespread the problem was in the past. What he particularly wanted to investigate was how ichthyosaurs adapted to the problem of decompression over the 150 million years. To this end, he and his colleagues traveled the world’s natural-history museums, looking at hundreds of ichthyosaurs from the Triassic period and from the later Jurassic and Cretaceous periods.
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If ichthyosaurs did evolve an anti-decompression means, they clearly did so quickly—and, most strangely, they lost it afterwards. But that is not what Dr Rothschild thinks happened. He suspects it was evolution in other animals that caused the change.
Whales that suffer the bends often do so because they have surfaced to escape a predator (捕食動(dòng)物) such as a large shark. One of the features of Jurassic oceans was an abundance of large sharks and crocodiles, both of which were fond of ichthyosaur lunches. Triassic oceans, by contrast, were mercifully shark- and crocodile-free. In the Triassic, then, ichthyosaurs were top of the food chain. In the Jurassic and Cretaceous, they were prey (獵物) as well as predator—and often had to make a speedy exit as a result.
【小題1】Which of the following is a typical symptom of the bends?

A．A twisted body. B．A gradual decrease in blood supply.
C．A sudden release of nitrogen in blood. D．A drop in blood pressure.
【小題2】The purpose of Rothschild’s study is to see _______.
A．how often ichthyosaurs caught the bends
B．how ichthyosaurs adapted to decompression
C．why ichthyosaurs bent their bodies
D．when ichthyosaurs broke their bones
【小題3】Rothschild’s finding stated in Paragraph 4 _______. 
A．confirmed his assumption B．speeded up his research process
C．disagreed with his assumption D．changed his research objectives
【小題4】Rothschild might have concluded that ichthyosaurs _______.
A．failed to evolve an anti-decompression means
B．gradually developed measures against the bends
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科目：高中英語 來源： 題型：閱讀理解

Research suggests that a newly-identified gene known as insomniacs(失眠癥患者) may play a role in keeping us asleep. By cloning and testing this gene in about 21,000 fruit flies, Rockefeller University researchers say they have discovered an entirely new mechanism (機(jī)制) by which sleep is controlled.
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“The results showed a great loss of both the time that the flies’ sleep lasted and their ability to remain asleep after they slept,” says researcher Nicholas Stavropoulos.
The researchers also examined the link between sleep and lifespan, finding that flies with mutations to the insomniac gene lived only about two-thirds as long as unchanged flies. But when the scientists removed insomniac only in neurons（神經(jīng)細(xì)胞）---allowing it to remain in the rest of the flies’ bodies---this difference disappeared; the resulting animals slept poorly but lived just as long.
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Although flies and humans would appear to have little in common when it comes to lifestyle, scientists say that the mechanisms of sleep and wakefulness are likely to be quite similar.
“Sleep is a fundamental behavior in all animals, and it is poorly understood from a scientific standpoint, says Stavropoulos. This work could prove useful in understanding and treating sleep disorders”
【小題1】The text is mainly about____.

A．the progress in cloning fruit flies
B．the methods of cloning fruit flies
C．the link between gene and lifespan
D．the influence of a gene on the ability to sleep
【小題2】According to paragraph2, the mutant flies________.
A．slept about 5 hours a day
B．had problems waking up
C．didn’t seem sleepy at all
D．could not fall asleep
【小題3】We can conclude from the text that________.
A．sleep and health go hand in hand
B．sleep can be controlled by humans
C．research into sleep is very fruitful
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