Read the following article and select the best answer. Article: Does stress cause gray hair? Many people believe that tension and stress can cause your hair to lose its color.In fact,it is an old wives tale that being upset all the time can result in premature graying.Here is a closer look at this situation and why some believe that this old wives tale could be true. As one ages,the hairs on the head also age.In fact,just about everything on the human body begins to show signs of wear and tear after a while.The joints wear and become stiff and skin wears and becomes wrinkled.Hairs on the head grow and eventually die.They are replaced,but in the process something else happens. When new hairs are replaced,the color or pigment is also added to them.However,as one ages,this pigment becomes less and less available.At first,hairs will have a limited amount of pigment and they will appear to be grayish in color.In time,they will lose all of their pigment and will be white.Many things are known to cause graying.and genetics is a very powerful factor.If one of your parents turns gray at an early age,there is a good chance that you will too.Some people begin the graying process in high school,while others may be over the age of forty. Constant worry and tension can have many harmful effects on the human body.It is a known fact that stressful times can cause one to suffer hair loss.It would make sense that if it can cause these problems,perhaps it also may contribute to graying.However,there is no sound evidence to support this. On the other hand,many medical professionals believe that there may be a link:between graying and a constant state of anxiety or tension.Does stress cause gray hair? There is no scientific evidence to support the theory,but it is best to avoid stressful situations. Question: From the passage we can infer that _ . - stress causing gray hair is still in question - gray hair has nothing to do with tension. - stressful situations can be of benefit. - sound evidence has been found.
stress causing gray hair is still in question
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Read the following article and select the best answer. Article: Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin colour. The gene comes in two versions, one of which is found in 99 per cent of Europeans. The other is found in 93 to 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science. Scientists have changed the colour of a dark-striped zebra fish to uniform gold by inserting a version of the pigment gene into a young fish. As with humans, zebra fish skin colour is determined by pigment cells, which contain melanosomes . The number, size and darkness of melanosomes per pigment cell determines skin colour. It appears that, like the golden zebra fish, light-skinned Europeans also have a mutation in the gene for melanosome production. This results in less pigmented skin. However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebra fish genes. Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun, which can cause skin cancer. But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng. Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin colours, said Cheng. The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin colour without damaging it like chemical treatment done on Michael Jackson. Question: The passage is probably taken from _ . - a novel - a science report - a story book - a science fiction
a science report
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Read the following article and select the best answer. Article: Say you're in the supermarket parking lot, holding your baby, bags of goods, and trying to open your car. A stranger walks up and says,"Here, let me hold your baby."Should you let him? According to a new New York University study, knowing whether or not to trust someone is so important that we can tell whether a face is trustworthy before we even consciously know it's there. The researchers knew from previous studies that people are fairly similar when it comes to how they judge a face's trustworthiness. They wanted to find out whether that would be true if people only saw a face for a quick moment -- an amount of time so short that it would prevent making a conscious judgment. To carry out their study, the researchers monitored the amygdala of 37 volunteers while showing them 300 faces for 33 milliseconds each. Those faces had already been tested with a different set of 10 subjects, who saw them for much longer. In those earlier tests, people agreed about whether to trust each face. In this new study, fascinatingly, different parts of the amygdala lit up when a subject saw an untrustworthy face and a trustworthy one -- and it lit up more when the face in question was suspicious . "Faces that appear likely to cause harm are suddenly tracked by the amygdala, so it could then quickly change other brain processes and make fast responses to people -- approach or avoid,"says Jon Freeman, the study's senior author."Our talents for making instant judgments could either come from birth or be learned from the social environment." So should you trust the guy in the parking lot? Your brain already knows. Question: The amygdala lit up more clearly when people . - came across a neutral face mask - saw an untrustworthy face - met a reliable person - saw a familiar face
saw an untrustworthy face
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Read the following article and select the best answer. Article: CANYOUIMAGINEHOWHARDITWOULDBETOREADSENTENCESLIKETHIS? Every one of us gets so used to punctuation marks that not many of us give them a second thought. Actually, the ancient Greeks wrote this way. The lack of punctuation marks probably didn't bother good readers, though. As they read, they just put pauses where they fit best. Also at this time, sentences switched directions. A sentence read from left to right. The next one read right to left, and then left to right again, etc. The ancient Romans sometimes punctuated like this: They * put * something * that * can * separate * words * in * a * sentence. The word punctuation actually comes from this idea and the Latin word punctum, which means a dot. When the 5thcentury arrived, there were just two punctuation marks: spaces and points. The spaces separated words while the points showed pauses in reading. Then in the 13thcentury, a printer named Aldus Manutius tried to standardize punctuation. He always used a period for a complete stop at the end of a sentence. He used a slash (/) to indicate a short pause. Over time, that slash was shortened and curled, and it became the modern comma . Since that time, other marks have enlarged the punctuation family. The exclamation mark comes from the Latin word io. It means "exclamation of joy." The question mark originally started out as the Latin word questio, meaning question. Eventually, scholars put it at the end of a sentence to show a question. Punctuation even keeps changing nowadays. New marks are coming into existence, and old punctuation marks are used in new ways. Take for example the "interrobang". This 1962 invention combines the question mark and exclamation mark for times when writers want both. For example, "She did what?" or "How much did you pay for that dress?" Obviously, the interrobang is not widely used or recognized yet, but its invention shows that English is not yet finished with its punctuation. Question: The passage is developed _ . - by time - by space - by comparison - by importance
by time
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