第二部分 阅读理解（共15小题；每小题2分，满分30分）
请认真阅读下列短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。
A
Riding your bike regularly not only gets you where you want to go faster than on foot, but protects you against a variety of diseases and makes you feel better.
Cycling is good for your health.
Everyday cycling is an effective and enjoyable form of aerobic exercise. This is the type of exercise that is most effective at promoting good health. For example, cycling reduces the risk of serious conditions such as heart disease, high blood pressure, obesity and the most common form of diabetes(糖尿病).
A study suggest that new cyclists covering short distances can reduce their risk of death by as much as 22%. Cycling helps us with weight loss.
Cycling helps to lose weight because it burns the energy supplied by a chocolate bar or a couple of alcoholic drinks in an hour. A 15-minute bike ride to and from work five times a week burns off about 11 pounds of fat in a year. That kind of cycling pattern also meets the Government’s latest target on exercise: we should take part in some physical activity that leaves us out of breath for at least 30 minutes five times a week.
Cycling can improve your mood.
Cycling has positive effects on how we feel too. Proper exercise has been found to reduce levels of depression and stress, improve moods and raise self-respect.
Cycling can help to maintain strength and coordination(协调).
There can also be indirect benefits in terms of reducing injuries from falls, which can lead to serious disability, especially in older people. The strength and coordination that regular cycling brings make them less likely. Physically active older people have much reduced rates of broken bones.
If you are worried about traffic fumes, there may be no need. Cyclists and walkers actually absorb lower levels of pollutants from traffic fumes than car drivers.
I will leave you with my personal bike motto in the hope that it can help you become inspired to go cycling. When it is cold outside, ride faster to warm up; when it is hot outside, ride faster to create a breeze. Happy pedaling! 61. How does the author convince readers of the benefits of cycling? A. By providing an exact figure B. By making comparisons
C. By offering detailed explanations D. By analyzing cause and effect
62. What’s the authors purpose of writing this passage? A. To show why people prefer cycling to driving B. To encourage more people to give bike riding a try C. To confirm what has long been believed about cycling D. To clarify some misunderstanding of fitness and cycling
B
Ohio---Lake Erie, the fourth largest lake of North America’s five Great supplies fresh drinking water to an estimated 11 million people in Ohio, Michigan and South Ontario, Canada.
Yet sometimes pollution, both from industrial waste and farm-chemical runoff, leaves large areas of the lake covered in half-meter-thick layers of green slime(黏液). Scientists blame a lot of chemicals entering the water, which has caused pollution.
To find out where these chemicals come from, the Ohio Department of Natural Resources has been studying data from its network of 14 water-quality monitoring stations installed along the rivers that flow into the Lake Erie basin. At one point, water from the small stream is diverted into pipe where it is pumped into the testing station. “We’ll have a sample a day, year round so that really pins down what the chemistry is like,” says Dave Baker of Ohio’s Heidelberg University, who took charge of the monitoring stations for the Department of Natural Resources. The U.S. Environmental Protection Agency, the federal government’s pollution watchdog, requires point sources, such as factories, to monitor and report their discharges(排出物). So Baker is looking for where the other sources of pollution come from.
“If there are problems in Lake Erie, we want to know where it’s coming from and make sure we’re putting resources to solve the problem properly,” Baker says. “It’s stations like this that help do that.”
In this case, a primary source of the pollution turns out to be chemical fertilizers that wash off farmland during rainstorms.
Because farmers and ranchers believe fertilizers are essential to high crop yields, they would like to use them. However, the USDA’s Natural Resource Conservation Service isn’t asking them to abandon farm chemicals, but rather to use them more sparingly(慎用地) so that they don’t run off the land when it rains.
Another technique for reducing farm chemical pollution of Lake Erie is cover-crop farming. After the harvest, farmers plant a second quick-growing crop to reduce erosion. The deep-rooted plants, such as rye or turnips, help to
cover the soil, allowing worms and fungi to work their magic and helping the soil to absorb more water and nutrients. 63. Who provides data from Lake Erie? A. The water-quality monitoring stations. B. Natural Resource Conservation Service. C. The Ohio Department of Natural Resources. D. The U.S. Environmental Protection Agency.
64. The underlined phrase “pin down” in Paragraph 5 means “___________”. A. looks through B. explains exactly C. keep a record of D. show clearly 65. What causes the pollution in Lake Erie? A. Animal waste from nearby farms. B. Waste water from a nearby factory. C. Chemical fertilizers from the fields. D. Pesticide farmers used to kill locusts.
66. What is the purpose of planting quick-growing crops? A. To prevent worms from eating crops. B. To increase the harvest of the farmers.
C. To make full use of chemical fertilizers in the soil. D. To keep the soil from being washed away.
C
Editing humans’ DNA
If you could change your child’s DNA in the future to protect them against disease, would you? it could be possible because of technology known as CRISPR-Cas, or just CRISPR.
CRISPR involves a piece of RNA, a chemical messenger, designed to work on one part of DNA; it also uses an enzyme (酶) that can take unwanted genes out and put new ones in, according to The Economist. There are other ways of editing DNA, but CRISPR will do it very simply, quickly, and exactly.
The uses of CRISPR could mean that therapies(疗法) are developed for everything from Alzheimer’s to cancer to HIV. By allowing doctors to put just the right cancer-killing genes into a patient’s immune system, the technology could help greatly.
In April scientists in China said they had tried using CRISPR to edit the genomes (基因组) of human embryos.
Though the embryos would never turn into humans, this was the first time anyone had ever tried to edit DNA from human beings. With this in mind, the US’ National Academy of Sciences plans to discuss questions about CRISPR’s ethics (伦理问题).
For example, CRISPR doesn’t work properly yet. As well as cutting the DNA it is looking for, it often cuts other DNA, too. In addition, we currently seem to have too little understanding of what DNA gives people what qualities. There are also moral(道德的) questions around “playing God”. Of course, medicine already stops natural things from happening —— for example, it saves people from infections. The opportunities to treat diseases make it hard to say we shouldn’t keep going.
A harder question is whether it is ever right to edit human germ-line (种系) cells and make changes that are passed on to children. This is banned(禁止) in 40 countries and restricted(限制) in many others. However, CRISPR means that if genes can be edited out, they can also be edited back in. It may be up to us as a society to decide when and where editing the genome is wrong.
Also, according to The Economist, gene editing may mean that parents make choices that are not obviously in the best interests of their children: “Deaf parents may prefer their children to be deaf too; parents might want to make their children more intelligent at all costs.”
In the end, more research is still needed to see what we can and can’t do with CRISPR. “It’s still a huge mystery how we work,” Craig Mello, a UMass Medical School biologist and Nobel Prize winner, told The Boston Globe. “We’re just trying to figure out this amazingly complicated thing we call life.” 67. What is the article mainly about?
A. How CRISPR was developed by scientists. B. What we can and can’t do with CRISPR.
C. The advantages of CRISPR and arguments about its ethics.
D. Chinese scientists’ experiment of using CRISPR to edit human embryos. 68. It can be concluded from the article that CRISPR ________. A. allows scientists to edit genomes for the first time B. could be helpful in the treatment of cancer and HIV
C. is a technology that uses an enzyme to work on RNA and DNA
D. has proven to be the most effective way to protect children against diseases 69. According to the article, the technology of CRISPR ________.
A. is very safe because it only cuts the DNA it is looking for
B. is banned in 42 countries and restricted in many others C. could cause parents to make unwise choices for their children
D. could help us discover the link between DNA and the qualities it gives people 70. What is the author’s attitude toward CRISPR?
A. Supportive. B. Worried. C. Negative. D. Objective.
D
Tradition has it that boys are good at counting and girls are good at reading. So much so that Mattel once produced a talking Barbie doll whose stock of phrases included “Math class is tough!”
Although much is made of differences between the brains of adult males and females, the sources of these differences are a matter of controversy. Some people put forward cultural explanations and note, for example, that when girls are taught separately from boys they often do better in subjects such as maths than if classes are mixed. Others claim that the differences are rooted in biology, are there from birth, and exist because girls’ and boys’ brains have evolved to handle information in different ways.
Luigi Guiso of the European University Institute has just published the results of a study which suggests that culture explains most of the difference in maths, at 1east.In this week’s Science, they show that the gap in mathematics scores between boys and girls virtually disappears in countries with high levels of sexual equality, though the reading gap remains.
Dr. Guiso took data from the 2003 OECD Programme for International Student Assessment. On average, girls’ maths scores were lower than those of boys. However, the gap was largest in countries with the least equality between the sexes, while it vanished in countries where the sexes are more or 1ess equal to one another. The researchers also did some additional statistical checks to ensure the correlation was material. They say their data therefore show that improvements in maths scores are related not to economic development, but directly to improvements in the social position of women. However, the gap in reading scores not only remained, but got bigger as the sexes became more equal. Average reading scores were higher for girls than for boys in all countries.
This suggests an interesting paradox. At first sight, girls’ rise to mathematical equality suggests they should be invading maths-heavy professions such as engineering—and that if they are not, the implication might be that prejudice is keeping them out. However, as David Ricardo observed almost 200 years ago, economic optimisation is about comparative advantage. The rise in female reading scores a longside their maths scores suggests that female comparative advantage in this area has not changed. According to Paola Sapienza, a professor of finance at Northwestern University in Illinois who is one of the paper’s authors, that is just what has happened. Other studies of