北京英语统一考试 2013.05.11 Passage 1
Is that 6 a.m. workout getting in the way of good sleep? Don’t think your fat cells won’t notice. A new study published in The Annals of Internal Medicine (a medical journal) finds that inadequate shut-eye has a harmful effect on fat cells, reducing their ability to respond to insulin (胰岛素) by about 30 percent. Over the long-term, this decreased response could set the stage for type-2 diabetes (a medical condition in which someone has too much sugar in his or her blood), fatty liver disease and weight gain.
The study adds to a growing body of evidence that there’ “an intimate relationship between the amount of sleep we get and our ability to maintain a good, healthy body weight,” says sleep expert Helene Emsellem, director of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland. (76) But Americans don’t seem to be getting the message that we need seven to nine hours par night. More than 1 in 5 of us, according to a report from the Centers for Disease Control and Prevention, is getting six or fewer hours of sleep per night, on average.
So how did researchers study fat cells in the Annals paper? Matthew Brady of the University of Chicago and a group of colleagues selected and persuaded seven volunteers to take part in the research project. They were all young, thin and healthy and agreed to sleep for eight nights in a sleep lab. “For four nights they were allowed to stay in bed for 8.5 hours a night,” says Brady. Then, a month later, they came back for four additional nights——but this time they were allowed just 4.5 hours of sleep per night. And after each visit, researchers got a sample of their fat. (77) Brady explains that the fat cells responded significantly to the loss of sleep. “I was very surprised to be honest,” he says.
Bad things can happen when fat cells become less responsive to insulin. “Fat cells are actually your friend,” he says. “They’re there to store lipids (血脂).” When lipids stay inside the cells, your body can utilize the fat when you’re exercising or sleeping or going about your day. “However, when fat cells stare to become insulin resistant, the lipids star to leach out of the fat cells and rise in the bloodstream,” Brady says.
1. According to the passage, lack of sleep for a long while can probably lead to all of the following EXCEPT_____.
A. heart disease B. weight gain C. diabetes D. liver disease 2. The main idea of the third paragraph is_____ A. how to write a medical research paper B. how to avoid sleep loss C. how the research was conducted
D. how to conduct a medical experiment
3. What does the “leach” in the last paragraph probably mean? A. Leap. B. Lead. C. Lean. D. Leak.
4. Which of the following is NOT TRUE according to the passage?
A. We will be in trouble if our fat cells become less responsive to insulin. B. More and more studies are done to study the lind between sleep and weight. C. More than 20% of Americans are not getting enough sleep. D. Fat cells are there to help us maintain a good health.
5. Which of the following is an appropriate title for this passage? A. Poor Sleep May Lead to Too Much Stored Fat and Disease B. Sleep Experts Had Exciting Findings in a Fat Study C. Americans Should Have More Than Six Hours of Sleep D. Bad Things Happen if Fat Cells Become Our Friend
Passage 2
The top of the world is a wonderland. In winter, the temperature often falls to -30°F and the sun never rises. The ocean is surrounded by frozen ground. There are few people or trees, but to polar bears, the Arctic(北极)is home.
(78) Polar bears have thick fur, big paws and other features that make them well prepared for life in their tough environment. In fact, they need the Arctic sea ice for survival. But climate change is causing larger and larger areas of summer sea ice to melt(融化). Experts say that if warming patterns continue, the Arctic could be free of summer sea ice by 2050. That may cause two-thirds of the world's 20,000 polar bears to be gone by then too.
Polar bears can't survive for long on land. Seals are their main source of food. The only place where polar bears can hunt seals is on the ice. (79) Although these bears are strong swimmers, they are no match for lightning swift seals in the water. A polar bear has brilliantly clever strategies to overcome this disadvantage. In winter the bear waits motionless beside a seal's breathing hole, which is a narrow tunnel through the ice. Often many hours pass before the seal
comes up for air and the bear kills it with a powerful blow of its paw. In summer, the polar bears that live on land eat very little and wait for the sea ice to return.
With the sea ice forming later in the year and melting earlier, polar bears do not have enough opportunity to hunt and eat. Less sea ice makes it harder for the bears to catch the seals. The bears must swim longer distances between ice packs(大片浮冰), and they can't always make it. The ice is also getting thinner. These conditions can cause polar-bear cabs to become separated from their mothers, who provide them with food.
Steven Amstrup is the chief scientist of Polar Bears International. The group aims to save the bears and their home. \situation, the better the chance we'll alter our warming path in time to save them,\ 6. Which is the best title for the passage?
A. Climate Change in the Arctic B. How to Protect the Environment C. The Arctic Ts Home to Polar Bears D. Polar Bears in Danger 7. Where do polar bears usually hunt seals? A. On land B. In open water.
C. In openings in the sea ice. D. At the bottom of the sea.
8. The word \ A. adults B. babies C. hunters D. enemies
9. According to the passage, which of the following statements is TRUE?
A. Starving polar bears are increasingly coming into villages, where they may be killed either for food or safety.
B. Polar bears can spend their entire lives on land if the sea ice melts completely. C. Two-thirds of the world's polar bears may disappear by 2050 as global warming continues. D. The growing distance between ice packs is not a problem for polar bears, because they are excellent swimmers.
10. What's the mission of Polar Bears International? A. Saving energy.
北京市成人本科学士学位真题(2013.5)
