Many science fiction stories tell about explorers arriving in a new world. The explorers then use some kind of high-tech device to test for breathable air or signs of life. But here on Earth, science fiction is becoming reality through a new sampling technology called environmental DNA, or e-DNA for short. Scientists can use it to identify rare or invasive species, study bio-diversity or estimate fish populations with just a little air or water.
Ryan Kelly is an ecologist at the School of Marine and Environmental Affairs at the University of Washington in Seattle. He works in a laboratory there with other researchers. They study the genetic material released by living creatures. “Essentially we can take a sample of soil or air — and in our case — water, and we can sequence（to arrange the order of genes）the DNA out of it and tell you what is there.”
Ryan Kelly says he and his research team are studying water samples collected from Puget Sound. He says the cost of gene sequencing has “been reduced greatly in recent years.” That makes DNA testing more widely available.
Environmental DNA can be used in two ways. One is to identify the creatures that live in a certain place. The other is to confirm the presence or lack of a specific creature.
Caren Goldberg heads the new e-DNA lab at Washington State University in Pullman, Washington. She is one of the first biologists in the northwestern United States to take the technology from the testing phase to actually using it.
“It is extremely useful for species that are really hard to find. I have spent many hours looking for species that I was pretty sure were there — looking under rocks, looking in water, doing all kinds of surveys.”
Caren Goldberg sees e-DNA as a way to get answers more efficiently, safely and with less destruction compared to traditional survey techniques. Until recently, scientists depended on diving deep, netting or using an electric current to temporarily catch fish.
“We’re absolutely at this point where proof-of-concept has been established. I don't think everyone necessarily is ready for it yet, but I think the majority of people are.”
This newer way to identify what lives in the environment is becoming popular around the world. Animal experts in Vietnam are using the e-DNA to find the last, wild Yangtze giant softshell turtles. One researcher on the Caribbean island of Trinidad is using the sampling technology to find endangered golden tree-frogs. And in Madagascar, it is being used to identify amphibian diseases.
Ms. Goldberg has used e-DNA testing to confirm the local extinction, disappearance, of a leopard frog in the American state of Idaho. She has also been asked to document the spread of the New Zealand mud-snail in the state of Washington. The creature has been found in lakes and other waterways across the state.
Now, the U.S. Bureau of Land Management wants Caren Goldberg to look for the Columbia spotted frog in two other western states. The rare amphibian is a candidate for the federal government's threatened species list.
Scientists working with the technology say they do not expect robots to replace field biologists anytime soon. But the old-fashioned field work could soon be more targeted.
A related research goal is to show how long environmental DNA can last and how far it can travel in different environments.
1.Paragraph One is intended as _____ of the passage.
A. the main idea
B. the introduction of the topic
C. a supporting detail of the main idea
D. a contrast of the main idea
2.What has made E-DNA magic is that with E-DNA_____.
A. you are likely to find information about a species with a little air, water, or soil
B. some kind of high-tech device can be used to test for breathable air or signs of life
C. you are able to get answers more efficiently, safely though with more damage
D. the cost of gene sequencing has been reduced greatly in recent years.
3.So far, the technique of E-DNA has NOT helped scientists search for ______.
A. wild Yangtze giant soft-shell turtles
B. endangered golden tree-frogs
C. the local extinction of a leopard frog
D. the spread of the New Zealand mud-snail
4.Despites its advantage, we are still not sure of something about E-DNA. That is _____ .
A. the lasting time and the spreading area of E-DNA
B .the lasting time of E-DNA and too many species for E-DNA
C. too many candidates for E-DNA and the lasting time of E-DNA
D. robots and old-fashioned field work’s replacing E-DNA
5.The passage can be sorted as a(n) _____.
A. science fictionB. experiment report
C. science reportD. bio-diversity discovery
Have you seen a historical film recently? Do you think it was accurate? Some say that there is no such thing as a historical film. In many cases, Hollywood film-makers simply change the facts. Just look at these supposedly “historical” films.
1. The Patriot
The film was released in 2000 and was directed by Ronald Emmerish and starred Mel Gibson. It is set near Charleston, South Carolina, during the American Revolutionary War(1775—1783) and follows the story of Benjamin Martin and his fight for American freedom against the British. The film was criticized for inventing and exaggerating British cruelty. The most criticized scene was one showing the burning of a church containing people of the town, of which there is no historical record. Another historical inaccuracy was the description of American-owned slaves being freed to serve with the American forces. In reality, many slaves ran away from their American owners and fought with the British against the Americans.
2. Brave Heart
The film(1995) starred Mel Gibson was directed by Toby Reisz. It is based on the life of Scottish national hero William Wallace and his fight against English rule in Scotland during the 13th century. The film includes an affair between William Wallace and Princess Isabella (based on Isabella of France). The film implies she is a mother-to-be when William Wallace will be killed. However, historically, the real Isabella was a child of nine still living in France at this time, never having met Wallace. The film also caused controversy because of its anti-English nature. Apparently, when the film was shown in Glasgow, there was a loud noise made by happy American audience.
3. U-571
This 2000 film was directed by Jonathan Mostow and starred Mathew MacConaughey, Havey Keitel and Jon Bon Jovi. It took place during the Second World War(1939—1945). In the film, a German submarine(warship underwater) is boarded in 1942 by American soldiers who made themselves up as Germans. They took away the German submarine’s code-language machine, which, in the film, helps the Americans get many secret messages from Germany. However, the film was heavily criticized because it was actually the British who got the machine in May 1941 when they boarded U-110. The movie was also criticized for showing a scene where the U-boat sailors killed American sailors in the water after their ship sunk, which is, in 99% cases, impossible to happen.
4. The 300 Spartans
The latest controversy surrounds the film The 300 Spartans. The film (directed by Zack Synder) tells the story of the battle between the Greeks and Persians in 480 BC. It is regarded as a key event in the birth of western democracy(民主) by some historians. In the film, 300 Spartans under the king fight against the enemies, 120,000 Persians led by Emperor Xerxes. The tiny Spartan forces repeatedly gain advantage over the invaders. These actions delays the Persians’ attack and gives the Greek armies enough time to prepare for the defense of Athens. But the Iranians (modern-day Persians) aren’t happy with the film. They say the film describes them as savage, killing-loving, and war-loving.
1.This article mainly _____.
A. praises four “historical” films
B. shares with us four great movies
C. tells the readers about the inaccuracy of four “historical” films
D. expresses the writer’s positive attitude towards the “historical” films
2.As far as time is concerned, the war in _____ broke out earliest.
A. The 300 SpartansB. U-571
C. The PatriotD. Brave Heart
3.Mel Gibson, a great American actor, starred in _____.
A. The Brave Heart and U-571
B. The Patriot and Brave Heart
C. The 300 Spartans and Brave Heart
D. The Patriot and The 300 Spartans
4.The passage probably comes from a(n)_____.
A. film posterB. fashion magazine
C. film reviewD. tour guide
Many families take their children on vacation. They will usually travel for a few days or weeks during school breaks. But Julie and Tim Rivenbark planned a longer vacation with their two children—the Rivenbark family is on a one-year trip around the world. They plan to visit 30 countries in all.
Right now, the four travellers are about halfway through their trip. Ms. Rivenbark says they are trying to see as much of the world as they can. She says “we have been through Europe, southern Africa, now we are kind of working our way through Asia. So we have been to a bunch of big cities, like Dubai, Johannesburg, Rome and Bangkok.”
The family has also spent time floating in kayaks(long narrow boats) in Italy, flying in hot air balloons in Myanmar, hiking to the Everest Base Camp in Nepal and going on a journey to see or hunt animals in South Africa.
Mr. Rivenbark says the family has also ridden on ostrich birds, elephants, and camels. But, he says, one of the most interesting experiences of the trip has been meeting new people.
“People have been extremely friendly, very welcoming and love our kids—interacting with them and their reaction to see our kids enjoying themselves in their country.”
Eleven-year old Tyler says he has enjoyed learning about the people they have met. “I learned in Africa that people have very different lifestyles compared to Americans.” His sister, 9-year-old Kara, discovered that she liked Thai food.
Ms. Rivenbark says that the extended trip teaches the children a lot more than short visits would have. “I think that the longer we travel, the more impact it has on how they see the world. I can see them changing more than they can see themselves.”
It took the family a year to prepare for the trip. They had to sell their house and cars. Ms. Rivenbark quit her job and her husband is using unpaid leave. They carry small bags filled with lightweight clothing and whatever else they need. Ms. Rivenbark says she enjoys being able to carry everything she needs on her back. She says she does not miss the things she has back home. “What has become more important is making these memories as a family and taking those with us instead.” Tyler and Kara each have iPads so they can communicate with teachers to stay current with their schoolwork. Tyler is also creating a 365-day video blog.
The Rivenbarks will continue to head east for the next six months. They plan to visit Laos, Cambodia, Vietnam, China and Australia. To follow their adventures, visit their website: earthtrekkers.com.
1.What makes the Rivenbarks different from other families is that _____.
A. they have their family trips during the children’s holidays
B. they have carefully planned their family trips for holidays
C. they plan to have a tour around the world without their children
D. they tour around the world with their kids not going to class
2.During the travel, _____ impressed the kids as well as the parents most.
A. floating in kayaks in Italy
B. hiking to the Everest Base Camp in Nepal
C. interacting with different people
D. riding on elephants and camels
3.The underlined word in Paragraph 7 extended is closest in meaning to _____.
A. expandedB. contented
C. shortenedD. intended
4.We can infer from the passage that _____.
A. It will take the family one year to prepare and finish their travel
B. The kids are finishing their current study with the help of the Internet
C. The family are likely to stay in Asia for the second part of their trip
D. To afford such a trip around the world is really something easy for the family
5.The passage is meant to _____.
A. share with the readers an extraordinary family trip
B. introduce some great parents and their jobs
C. remind us of the pleasure of getting close to nature
D. inform us of the benefits of travelling around the world
Life is a series of choices and we can’t always foresee the consequences.
Harry Saleem, an obese( too fat) man with too much money and power, faced a(n) . Outside his office waited his personal , bringing him the news about the only medicine that could save his life. On the other side of the world, one of his engineers waited for his decision on an important of business.
His secretary asked him she could bring the doctor in. The billionaire businessman made his . “No. let the fool wait,” answered Saleem, “business comes first.” the health problem caused by his huge weight, he was still about making money. He a fat finger, and one of his staffs to switch on a large television set.
On the screen appeared his engineer. They talked by satellite directly to each other although they were thousands of miles . “It’s all ready to explode, Mr. Saleen,” he said, “just one .” His engineer was standing above Pakan Valley in South America. A few months ago, it had been a rainforest. Then Saleem’s men came, cutting down all the valuable trees and the villagers to move out. the valley, a dam had been built. This would provide power for the factories that Saleem planned to build in that area. The factories would bring him great .
He saw no reason to delay. He ordered the engineer to press the button. There, in the valley, a cloud of dust rose, by a dull explosion. A large river changed its course and water flooded into the valley.
“Good, that’s that. Now, get that doctor in here,” he .
The doctor came in with a worried look and started to examine his patient. “You are doing very well, Mr. Saleen. The only medicine is saving your life. But the difficulty is getting more of it.”
“Can you get more? Money is no problem.” Saleen said. “Tell me what you need and we’ll get it.”
The medicine was made of a plant, which is . There is only one place in the world where the plant grows.”
“Where?” asked the businessman, .
The doctor smiled. “Well, luckily, the plant comes from one of the lands you own, sir. It comes from a place in South America, known as Pakan Valley.”
1.A. choiceB. opportunityC. consequenceD. problem
2.A. employeeB. secretaryC. doctorD. engineer
3.A. amazingB. interestingC. heart-breakingD. important
4.A. eventB. matterC. incidentD. accident
5.A. thatB. whetherC. untilD. unless
6.A. decisionB. mistakeC. promiseD. plan
7.A. BesidesB. ExceptC. InsteadD. Despite
8.A. addictedB. crazyC. interestedD. dying
9.A. aroseB. roseC. raisedD. aroused
10.A. beganB. stoppedC. hesitatedD. hurried
11.A. apartB. awayC. farD. aside
12.A. lookB. wordC. momentD. while
13.A. forcingB. askingC. forbiddingD. stopping
14.A. AboveB. AlongC. ThroughD. Across
15.A. profitsB. advantagesC. preferenceD. achievements
16.A. followB. to followC. followingD. followed
17.A. demandedB. recommendedC. commandedD. suggested
18.A. healthyB. wealthyC. worriedD. frightened
19.A. commonB. usualC. rareD. normal
20.A. delightedlyB. thoughtfullyC. impatientlyD. cautiously
—Things aren’t going too well financially, sir.
—You mean we’re _____ soon?
A. in the greenB. in the blue
C. in the redD. in the yellow
Parents and teachers always think students should spend more time on their studies, but students themselves think _____.
A. otherwiseB. insteadC. meanwhileD. moreover
