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题型:阅读选择 题类:常考题 难易度:普通

广东省深圳市龙岗区2019-2020学年八年级下学期英语期末测试卷

阅读理解

    Dogs are known for their sense of smell. They can find missing people and things. Now a study shows that the animal can even find bladder cancer (膀胱癌).

Cancer cells can produce chemicals with unusual smells. Scientists think dogs have the ability to smell these smells, even in very small amounts, in urine (尿).

    For example, a dog showed great interest in the growth of its owner's legs. The man was later found to have skin cancer. Carolyn Willis and some scientists trained different kinds of dogs for the experiment. The study used urine collected from bladder cancer patients (病人), from people with other diseases and from healthy people. Each dog was tested 8 times. In each test there were 7 examples for the dog to smell. The dog should show the one from a bladder cancer patient by lying down next to it.

    Their results later appeared on the British Medical Journal. In all, 36 bladder cancer patients and 108 other people attended. During the training, all the dogs even found cancer in a person who had been tested healthy before the study. Carolyn Willis said dogs could help scientists find the chemicals produced by bladder cancer. The information could then be used to develop machines to test for the chemicals. The team also plans to use dogs to help find other kinds of cancer.

(1)、How many kinds of urine were collected in the experiment?
A、One. B、Two. C、Three. D、Four.
(2)、Why did the writer give the detailed ex­periment in the third paragraph?
A、To introduce the first paragraph. B、To support the second paragraph. C、To teach us to do some experiments. D、To let us know the reason of the ex­periment.
(3)、What would the dog do when it found the right urine?
A、It would lie down next to its owner's feet. B、It would take the urine to the scientists. C、It would lie down next to the urine. D、It would make some noises.
(4)、What's the main idea of the passage?
A、Dogs have a good sense of smell. B、Dogs can help people become healthy. C、Dogs can be used in experiments. D、Dogs can smell cancer.
(5)、Who may be most interested in reading the passage?
A、Dog owners. B、Doctors. C、Pet lovers. D、Singers.
举一反三
 阅读理解

Scientists have made a "breakthrough" in handling nuclear fusion(核聚变). The US Department of Energy officially announced the milestone in fusion energy research.

For the first time, researchers created a nuclear fusion reaction that produced more energy than they put into the process. The experiment, conducted at Lawrence Livermore National Laboratory in California, generated 3.15 megajoules of energy, more than the 2.05 megajoules put into creating it.

Nuclear fusion works by forcing together two atoms—most often hydrogen—to make a heavier one—like helium(氦). This explosive process releases massive amounts of energy, the Department of Energy explains. Fusion is the opposite of fission(裂变), the reaction that powers nuclear reactors used commercially today.

Fusion occurs naturally in the heart of the Sun and the stars, providing these cosmic(宇宙的) objects with fuel. Since the 1950s, scientists have been trying to reproduce it on Earth inorder to make use of the so-called clean, cheap, and almost limitless electricity. According to the International Atomic Energy Agency, fusion generates four times more energy per kilogram than the fission used to power nuclear plants, and nearly 4 million times more energy than burning oil or coal. What's more, unlike fossil fuels, fusion doesn't release carbon dioxide—the greenhouse gas that's the main driver of climate change — into the atmosphere. And unlike nuclear fission, fusion doesn't create long-lived radioactive waste, according to the Department of Energy. But so far, nuclear fusion hasn't solved our energy problems on a grand scale.

The recent announcement is a huge step forward in nuclear fusion energy, but applying the technology at commercial scale is likely still years away. Chanda Prescod Weinstein, a theoretical physicist, pointed out that the process the Department of Energy uses requires tritium(氚), a rare and radioactive isotope(同位素) of hydrogen."It may yet convey important information that is ultimately transformative. We don't know yet,"Prescod Weinstein tweeted. Investors, including Amazon founder Jeff Bezos, have poured billions into the clean energy field trying to make fusion commercially workable, and the recent announcement is likely to continue that trend.

 阅读下面材料,从每题所给的A、B、C、D四个选项中选出最佳选项。

Have you noticed that time seems to pass more slowly when you're waiting in a long line? But when you're playing with your friends, hours seem like minutes. Of course, time is always passing at the same speed--but why does it sometimes feel different?

A study published in the Journal of Neuroscience (神经科学杂志)can tell us the answer. Lead author Masamichi Hayashi and his research team in the US found that it has to do with neurons(神经元)in our brains that are sensitive(敏感的)to time.

The researchers measured (测量)the brain activity of 18 adults who were asked to look at a picture on a screen for a certain period of time. They were then asked to guess how long they had been looking at the picture. They were likely to guess incorrectly when they were asked to stare at the picture for very long or very short periods of time. 

After looking at their brain activity, the researchers found neurons need a certain amount of time to pass signals. When they receive repetitive stimulation(重复的刺激) (such as staring at a screen), these neurons finally get tired and don't work well. It doesn't matter whether this amount of time is long or short, as long as the stimulation is repetitive. However, other neurons still work normally, causing a different experience of time.

When you stand in line or do some other repetitive tasks, such as math homework, your time-sensitive neurons get tired and cause you to feel like time is going slowly. But when you're doing something more high-speed, such as playing soccer, you experience in the opposite way. Either way, you can't always trust your brain when it comes to your experience of time.

 请阅读下面短文, 根据短文内容从每小题所给的 A、B、C、D四个选项中选出最佳选项

So far, China has successfully sent a large number of satellites(卫星) and spaceships into space. Space scientists have been greatly inspired(赋予灵感) by the old stories and ancient famous people when giving them names.

 Since thousands of years ago, Chinese people have dreamed of going to the moon. Chang' e flies to the Moon is one of the most popular stories. As you can see, China's first man-made satellite to circle around the moon was named Chang' e I. More interestingly, the moon rover(巡视器) was named after the Jade Rabbit, who is the partner of Chang' e in the story. These old stories carry people' s best wishes and dreams. With the development of science and technology, our scientists have made them come true.

 Kuafu Runs After the Sun is another story to show how much ancient Chinese people wanted to know about the unknown world. Now, Kuafu is going with the scientists to"visit" the sun, because we have a space project called Kunfu Mission.

 Besides the ancient stories, space scientists also get ideas from ancient famous people. For example, Mori, an ancient scientist, discovered that light travels in a straight line over 2,000 years ago. His discovery made space study take a big step at that time. So, China's first quantum(量子) science satellite was named Mozi, making China the first country in the world to achieve quantum communication between satellites and the ground.

 From such simple things as giving names to the satellites, we can see how great our traditional culture is and what influence it has on our modern science and technology(科技).

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