| Now medical researchers are discovering
a truism: "alcohol and tobacco do not mix." These two substances, both dangerous
to health, act synergistically, each making the other more powerful and thereby
causing worse damage than either would do alone. Because of this interaction, the person who both smokes and drinks heavily may be at a greater risk of becoming ill than one who drinks like a fish, but never smokes or who smokes like a chimney, but never drinks. To get an idea of how this synergism may work, consider what happens when a smoker lights up a cigarette. With each puff he inhales at least 4,000 different chemicals. These include toxic hydrogen-cyanide, carbon monoxide and nitrogen-dioxide gases, and four dozen compounds such as benzo pyrene and radioactive polonium 210. All are known as carcinogens. Most chemical vapor A. Because it may act as a dissolving agent. B. Because he is malnourished. C. Because the liver can’t dispose of alcohol D. Because the liver has to clean the toxins. [单项选择]Researchers discovered that plants infected with a virus give off a gas that（）disease resistance in neighboring plants.
A. contracts B. activates C. maintains D. prescribe [单项选择]Researchers are beginning to understand why lasting weight loss is so hard. They believe it has to do with damage to the part of the brain that’s involved in weight control.
If obese people stop overeating, switch to a healthful diet and start exercising, they lose weight. However, they may quickly gain it back again. The reason, say researchers, is not a lack of willpower but injury to brain cells, or neurons, in the hypothalamus (下丘脑)—a structure deep in the brain that helps control a number of body functions including appetite and weight. The notion that brain damage might play a role in body weight is not a new one, according to Michael Schwartz of the Diabetes and Obesity Center at the University of Washington in Seattle. Scientists have known for about five years that the hypothalamus of overweight animals—including humans—displays inflammation (炎症), a typical reaction to injury. But researchers, led by Schwartz, wanted to determine the role hypothalamus injury pla A. the man has an unhealthy diet and makes little exercise B. the brain cells in the hypothalamus suffer from damage C. the man is lack of willpower to keep on losing weight D. the body function of appetite is out of control [单项选择]Researchers found family influenced delinquency. Attachment and involvement were both (47)______ related to delinquency. Children who were more (48)______ to and involved with their parents were less involved in delinquency. The relationship between family process factors and delinquency was (49)______ — poor parenting increased the probability of delinquent behavior and delinquent behavior further weakened the relationship between parent and child. The impact of family variables appeared to fade as adolescents became older and more (50)______ from their parents.
Additionally, researchers (51)______ the relationship between educational factors and delinquency and drug use and found that weak school commitment and poor school (52)______ were associated with increased involvement in delinquency and drug use. School success was associated with resilience. Youth who (53)______ delinquency and drug use were more attached to school and teachers and had better performance scores than y
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Researchers have found that migrating animals use a variety of inner compasses to help them navigate. Some (1) by the position of the Sun. Others navigate by the stars. Some use the Sun as (2) guide during the day, and then (3) to star navigation by night. One study shows that the homing pigeon uses the Earth’s magnetic fields as a guide (4) finding its way home, and there are indications that various other animals, from insects to mollusks (软体动物), can also make (5) of magnetic compasses. (6) is of course very useful for a migrating bird to be able to switch to magnetic compass when clouds cover the sun; (7) it Would just have to land and wait for the Sun to come out again. (8) with the Sun or stars to steer by, the problems of navigation are more complicated (9) they might seem at first. For example, a worker honeybee (10) has found a rich source of nectar and pollen flies rapidly home to the hive to [单项选择]Researchers investigating brain size and mental ability say their work offers evidence that education protects the mind from the brain’s physical deterioration.
It is known that the brain shrinks as the body ages, but the effects on mental ability are different from person to person. Interestingly, in a study of elderly men and women, those who had more education actually had more brain shrinkage. "That may seem like bad news," said study author Dr. Edward Coffey, a professor of psychiatry and of neurology at Henry Ford Health System in Detroit. However, he explained, the finding suggests that education allows people to with stand more brain-tissue loss before their mental functioning begins to break down. The study, published in the July issue of Neurology, is the first to provide biological evidence to support a concept called the "reserve" hypothesis, according to the researchers. In recent years, investigators have developed the idea that people who are more educated A. running B. playing chess C. swimming D. playing football. [单项选择]
Researchers produced evidence to support what most of us already knew--that a cup of tea is the answer to any crisis. [简答题]American and Japanese researchers are developing a smart car that will help drivers avoid accidents by predicting when they are about to make a dangerous move.
The smart car of the future will be able to tell if drivers are going to turn, change lanes, speed up, slow down or pass another car. If the driver’s intended action could lead to an accident, the car will activate a warning system or override the move. (61)"By shifting the emphasis of car safety away from design of the vehicle itself and looking more toward the driver’s behavior, the developers believe that they can start to build cars that adapt to suit people’s needs," New Scientist magazine said. Alex Pentland of the Massachusetts Institute of Technology collaborated on the project with Andrew Liu who works for the Japanese carmaker Nissan. (62) Tests of their smart car using a driving simulator have shown that it is 95 percent accurate in predicting a driver’s move 12 seconds in 我来回答: 提交
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