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DNA left at a crime scene could be used in the future to build up a picture of an offender’s face, it was revealed tonight.
A first step towards genetic mugshots has been taken by researchers in the US who link specific DNA markers with face shape. To identify the genes, they focused on known mutations(突變) that cause changes of the face and head. Normal versions of these genes were found to influence individual features. For instance, one gene affected the lips, another the shape and configuration of bones around the eyes, and a third the appearance of the mid-face and skull. In total, 20 genes had “significant effects” on facial appearance.
Lead scientist Professor Mark Shriver, from Pennsylvania State University, said: “We use DNA to match to an individual or identify an individual, but you can get so much more from DNA. Currently we can’t go from DNA to a face, or from a face to DNA, but it should be possible.” The implications are far reaching, raising the possibility of creating a data bank of facial types based on genetic markers. DNA from a crime scene could then be used to produce a rough image of the face of an offender or victim. Such genetic mugshots may be more reliable than computer-generated “e-fits” based on witnesses’ recollections. Other uses of the technique might include proving the identity of fathers in paternity cases, or visualising our remote ancestors from fossil DNA.
The scientists wrote in the online journal Public Library of Science Genetics: “Such predictive modelling could be forensically useful; for example, DNA left at crime scenes could be tested and faces predicted in order to help to narrow the pool of potential suspects. Further, our methods could be used to predict the facial features of descendants, deceased ancestors, and even extinct human species. In addition, these methods could prove to be useful diagnostic tools.” The team developed a model which first established a range of physical face shapes from people of mixed West African and European ancestry from the US, Brazil and Cape Verde. Measurements were taken of thousands of point co-ordinates on grids placed over 3D images of the faces.
Statistical methods were then used to determine the relationship between facial differences and the effects of gender, ethnic ancestry and individual gene variants.
小題1:The underlined word “mugshots” in the second paragraph most probably means _________.

A．different faces

B．characteristics

C．pictures of faces

D．genders

小題2:What can be inferred from the passage?
A. DNA has been used to build up a picture of an offender’s face.
B. It may be much easier to catch criminals with the help of DNA.
C. In all, 20 genes had “significant effects” on facial appearance.
D. One gene can affect more than one part of your face.
小題3:According to Professor Mark Shriver, we know_________.

A．they can merely match to an individual or identify an individual

B．there is a possibility of going from DNA to a face

C．DNA could be used to produce a rough image of an offender’s face

D．this technology is more reliable than computer-generated “e-fits”

小題4:What is the most possible title of the passage?

A．Creating a data bank of DNA

B．Recognizing the DNA of criminals

C．Predicting the location of offence using DNA

D．Building image of offender’s face from DNA

Scientists at Royal Holloway, University of London  and Queen Mary, University of London have discovered that bees learn to fly the shortest possible route between flowers even if they discover the flowers in a different order. Bees are effectively solving the “traveling salesman problem”, and they are the first creatures found to do this.

The traveling salesman must find the shortest route that allows him to visit all locations on his route. Computers solve it by comparing the length of all possible routes and choosing the shortest, and it can keep computers busy for days. However, bees solve it without computer assistance using a brain the size of grass seed. Dr. Nigel Raine, from the School of Biological Sciences at Royal Holloway explains, “Bees solve traveling salesman problems every day. They visit flowers at multiple locations and because bees use lots of energy to fly, they find a route which keeps flying to a minimum. ”
The team used the computer to control artificial flowers to test whether bees would follow a route defined by the order in which they discovered the flowers or if they would find the shortest route. After exploring the location of the flowers, bees quickly learned to fly the shortest route.
As well as improving our understanding of how bees move around the landscape pollinating(授粉)crops and wild flowers, this research, which is due to be published in The American Naturalist, has other applications. Our lifestyle relies on networks such as traffic on the roads, information flow on the Web and business supply chains. By understanding how bees can solve their problems with such a tiny brain, we can improve our management of these everyday networks without needing lots of computer time. Dr. Raine adds, “Despite their tiny brains, bees are capable of extraordinary feats of behavior. We need to understand how they can solve the traveling salesman problem without a computer. ”
小題1: What would be the best title of the passage?

A．Bees help salesmen travel

B．Tiny-brained bees solve a complex mathematical problem

C．How bees discover the flowers

D．How to solve the “traveling salesman problem”

小題2:We may infer from the second paragraph that the “traveling salesman problem” 　　　.

A．can be solved by a computer easily

B．can’t even be solved by a computer

C．can puzzle both people and computers

D．remains to be solved by scientists

小題3: The main purpose of the last paragraph is to　　　.

A．provide further proof for the research

B．tell us how bees can fly the shortest route between flowers

C．tell us how the research about bees’ flying route was conducted

D．explain the importance of the research

小題4: It can be concluded from the passage that　　　.

A．a(chǎn)ll creatures are smarter than computers

B．the research about bees’ flying route can be applied to many fields

C．our networks are more complex than bees’ ones

D．with the help of the computer we can find out how bees can solve the “traveling salesman problem”

Has been a dream for 30 years but now the world’s first flying car is set to hit the roads this year.

Ever since the “Back to the Future” movies lit up our screens in the 1980s, designers have dreamt of cars that could take to the sky at the push of a button(按鈕). And now pilots can order their own “roadable” plane for just￡127, 000.
The plane, which has fold-out wings that span 17. 5 feet, can be up to 115 mph. Back on the land, it can also travel at “highway speeds” in car mode(模式).
Fuelling(加燃料)the 19 feet long plane couldn’t be simpler—you just drive it into a petrol station and fill it up.
A spokeswoman said, “You can keep your ‘light-sport airplane’ in your garage. But because it needs a short runway to take to the air, you will have to drive to your local airport, fly up to 460 miles, land and drive directly to your destination(目的地). You will always be ready to drive or fly. ”
The spokeswoman added, “Never let bad weather change your trip. You can simply divert(使轉(zhuǎn)向)and continue on the ground until the weather clears. ”
There’s no risk to you—this is only the chance for you to be the first at your home field to unfold(展開)your wings and fly into the future.
小題1:According to the text, the “roadable” plane　　　.

A．can fly in the sky at “highway speeds” in car mode

B．is a kind of car with fold-out wings

C．is a little difficult to fuel

D．can only travel on the highway

小題2:We can infer that in the “Back to the Future” movies　　　.

A．there are some skillful pilots

B．pilots have no cars to drive

C．pilots can’t afford a “roadable” plane

D．cars can fly in the sky

小題3:What does the underlined word “it” in the 5th paragraph refer to?

A．Light-sport airplane.

B．Your garage.

C．The local airport.

D．A petrol station.

小題4:The last sentence of the text aims to　　　.

A．call for people to buy the “roadable” plane

B．show people the use of the “roadable” plane

C．tell people only the “roadable” plane can fly in the future

D．a(chǎn)sk people to unfold their wings and fly into the future

小題5:If you meet with a thunderstorm in your “roadable” plane in the skies, you can　　　.

A．land in a nearby airport until it clears

B．turn back home until it clears

C．land and drive on the ground

D．fly high up to 460 miles

At first sight the planet Mars(火星)does not appear very welcoming to any kind of life. It has very little oxygen and water, the temperature at night is below 50 degrees and winds of 100 miles(161 kilometers)per hour cause severe dust storms. However, the surface of the planet seems to show that water flowed across it at some time in the past, and it is believed that there would be enough ice at the poles to cover the planet with water if it melted. Although there is no life on the Mars now, some scientists think there may have been some form of life a long time ago. At that time, the planet had active volcanoes(火山); the atmosphere was thicker and warmer; and there was water. In fact, in some ways the Mars may have been similar to the Earth, where life exists.

Some people believe that the Mars could support life in the future if the right conditions were produced. The first step would be to warm the planet using certain gases which trap the Sun’s heat in the planet’s atmosphere. With warmth, water and carbon dioxide, simple plants could begin to grow. These plants could slowly make the Mars fit to live on. It is judged that the whole process might take between
100, 000 and 200, 000 years. In the meantime, people could begin to live on the planet in a special closed environment. They would provide a lot of useful information about conditions on the Mars and the problems connected with living there.
小題1: According to the passage, the planet Mars has no　　　on it.

A．winds	B．dust
C．mountains	D．a(chǎn)nimals

小題2:It is believed that on the Mars now　　　.

A．there is a large amount of ice at the poles

B．there is a thicker and warmer atmosphere

C．there are some kinds of simple plants

D．there are many active volcanoes

小題3: What is the topic of Paragraph 2?

A．Certain gases should be used to warm the Mars.

B．Plants should be grown to make the Mars fit to live on.

C．The Mars could support life on right conditions in the future.

D．People could live on the Mars in a special closed environment.

小題4: The most suitable title for the passage is　　　.

A．No Life on the Mars

B．Study of the Mars

C．The Possibility of Life on the Mars

D．Future Conditions on the Mars

If you want to help children develop language and speech skills, UCLA researchers say, listening to what they have to say is just as important as talking to them.

The effect of a conversation between a child and an adult is about six times as great as the effect of adult speech input(輸入)alone, the researchers found. “Adults speaking to children helps language develop, but what matters much more is the interaction, ”said the study’s lead author, Frederick   Zimmerman, an associate professor in the School of Public Health at the University of California, Los Angeles.  The researchers also found that TV viewing didn’t have much of an effect—positively or negatively—as long as it wasn’t displacing conversations between an adult and a child.
The UCLA study included 275 families with children between 2 months and 48 months old.  They represented a variety of incomes and education.  The researchers found that, in an average day, children heard about 13, 000 spoken words from adults and participated in about 400 adult-child conversations a day.
Assessed separately, factors positively associated with language development included each additional 100 conversations a day and each 1, 000 words increase in the number of words spoken by adults and heard by children.  When looked at alone, TV was negatively associated with language development.  But, when these three factors were analyzed together, the only one that stood out was conversation between adults and children.
“The more a child speaks and interacts with an adult, the better idea a parent has about where the child is”, Zimmerman said. “Although it’s mostly done unconsciously, parents will provide feedback and correct mistakes.  They’ll also tailor their speech to the child.  Parents can give the children words by talking to them about what they’re doing, such as, ‘I’m putting on your pajamas now’.  But give your child the opportunity to talk, hopefully without the rest of the noise in the environment, ”she added. “If parents can carve out some conversation time—maybe at bath time or at dinner time—that’s a wonderful thing. ”
小題1: The researchers also found that TV viewing　　　　.

A．could have a positive effect on a child’s language development

B．had a little effect on a child’s language development

C．a(chǎn)ffected a child’s language development more negatively than positively

D．a(chǎn)ffected a child’s language development both negatively and positively

小題2:Frederick Zimmerman would probably agree that　　　　.

A．parents should let their children talk most of the time

B．children should watch TV programs selectively

C．the conversation between parents and children should be two-way

D．it’s no good for parents to correct their children’s mistakes when they are speaking

小題3: We can conclude from the last paragraph that　　　　.

A．parents should let a child repeat what he or she says

B．bath time or dinner time is the best chance for parents to talk to a child

C．parent-child conversation can be carried out at any proper time

D．parents should leave a child talking alone

小題4: What would be the best title for the passage?

A．Talk with kids, not at them

B．Let your children voice their own opinions

C．How to develop a child’s language ability

D．The importance of early child language development

小題5:The underlined word “tailor” in the last paragraph can be best replaced by　　　　.

A．control	B．improve
C．pass	D．a(chǎn)djust

　　Bananas are one of the world’s most important food crops. They are also one of the most valuable exports. Bananas do not grow from seeds. Instead, they grow from existing plants. Bananas are threatened by disease because all the plants on a farm are copies of each other. They all share the same genetic weaknesses. For example, the Cavendish banana is most popular in North American and European markets. However, some kinds of fungus organisms easily infect the Cavendish. Black Sigatoka disease affects the leaves of Cavendish banana plants. The disease is controlled on large farms by putting chemicals on the plants’ leaves. Farmers put anti-fungal chemicals on their crops up to once a week.

Another fungal disease is more serious. Panama disease attacks the roots of the banana plants. There is no chemical treatment for this disease. Infected plants must be destroyed. Panama disease has affected crops in Southeast Asia, Australia and South Africa. There is concern that it may spread to bananas grown in the Americas. This could threaten an important export product for Central and South America.
The International Network for the Improvement of Banana and Plantain supports research on bananas. The group has headquarters in France and other offices in the major banana-growing areas of the world. The group says that more research must be done to develop improved kinds of bananas. The group says that fungal diseases mainly affect only one kind of banana. In fact, there are five hundred different kinds of bananas. Food and Agriculture Organization of the United Nations has said that the Cavendish banana represents only 10% of world production.
The U. N. agency says farmers should grow different kinds of bananas. This protects against diseases that affect only one kind. Experts warn that disease may cause the Cavendish banana to disappear. This happened earlier to another popular banana because of its genetic weakness against disease.
小題1:What does this passage mainly tell us?

A．Bananas are the world’s most important food crops.

B．The risk to a popular banana shows need to grow other kinds.

C．There are five hundred different kinds of bananas.

D．How to grow bananas in different countries.

小題2:Bananas are threatened by disease because　　　.

A．they grow from seeds

B．they are one of the most valuable exports

C．the only way to prevent it is to put chemicals on their leaves

D．they have genetic weaknesses against disease

小題3: Panama disease　　　.

A．doesn’t belong to fungal disease

B．a(chǎn)ffects the leaves of banana plants

C．destroys bananas more seriously than Black Sigatoka disease

D．has spread to bananas all over the world

小題4: We can infer from Paragraph 3 that　　　.

A．the center of the group is in the US

B．the Cavendish banana covers only a small part of the yield of bananas

C．the key to solving the disease is to research all kinds of bananas

D．each fungal disease affects five hundred different kinds of bananas

　　Ten years ago, with only about 1, 000 pandas left in the world, China was desperately trying to clone(克隆)the animal and save the endangered species(物種). That was a move similar to what Texas A & M University researchers had been undertaking for the past five years in a project called “Noah’s Ark”(諾亞方舟).
Noah’s Ark was aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine, said there would be enough of the basic building blocks to reintroduce the species in the future.

It was estimated that as many as 2, 000 species of mammals, birds reptiles would become extinct in over 100 years. The panda, native only to China, was in danger of becoming extinct in the next 25 years.
This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They were then trying to implant the embryo into a host animal.
The entire procedure could take from three to five years to complete.
“The nucleus transfer(核子移植)of one species to another is not easy, and the lack of available(capable of being used)panda eggs could be a major problem,”Kraemer believed. “They will probably have to do several hundred transfers to result in one pregnancy(having a baby). It takes a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort, ”added Kraemer, who was one of the leaders of the project at Texas A& M, the first-ever attempt at cloning a dog.
“They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed. ”
At present, the project has worked. The number of the pandas has increased to more than 1, 500.
小題1:The aim of “Noah’s Ark” project was to　　　　.

A．make efforts to clone the endangered pandas

B．save endangered animals from dying out

C．collect DNA of endangered animals to study

D．transfer the nucleus of one animal to another

小題2: According to Professor Kraemer, the major problem in cloning pandas would be the lack of　　　　.

A．a(chǎn)vailable panda eggs	B．host animals
C．qualified researchers	D．enough money

小題3: The best title for the passage may be　　　　.

A．China’s Success in Pandas Cloning

B．The First Cloned Panda in the World

C．Exploring the Possibility to Clone Pandas

D．China—the Native Place of Pandas Forever

小題4:From the passage we know that　　　　.

A．Kraemer and his team had succeeded in cloning a dog

B．scientists tried to implant a panda’s egg into a rabbit

C．Kraemer would work with Chinese scientists in clone researches

D．a(chǎn)bout two thousand species would probably die out in a century

　　It was July 1976. An unmanned spaceship, Viking One, had arrived at Mars. On July 20th, the spaceship　　. Part of it continued toward a landing on the planet. It fell　　through the late afternoon Mars’ sky.
Forty kilometers above the planet, the thin　　began to slow its fall. Six kilometers above the planet a big parachute(降落傘)opened. The landing craft fell more slowly. Then, three rocket engines　　. And the landing craft set down　　on the surface. 　　in the Viking One Lander immediately sent a message to the earth. It said, “I am here. I am down safely. I am beginning my work. ”
The message　　at the speed of light. It took twenty minutes to reach the earth, more than three hundred and twenty million kilometers　　. Scientists and engineers at the control center　　.
Moments later, television receiver in the control center began to　　the first picture from Viking One. People at the center could see the feet of the landing craft sitting firmly on the　11　soil of Mars. Those pictures were our first　　look at the planet. They showed a red surface, full of rocks, with no sign of　　. It was our first look at a planet that is full of surprises, mysteries and promise. Viking One was launched toward Mars in August, 1975. The spaceship had two　　: an orbiter(軌道飛行器)and a lander(著陸器). The orbiter would circle　　Mars. It would take pictures of Mars’ surface. It would　　the atmosphere.
The　　would go down to the surface. It would carry　　to dig up and study soil and　　.
It also would report about any evidence of life on the planet. The lander would send this　　to the orbiter and then back to the earth.

小題1:	A．separated　　　　　　 B．a(chǎn)ppeared C．worked D．started

小題2:	A．correctly B．slowly C．quickly　　 D．directly

小題3:	A．a(chǎn)ir B．universe C．space D．a(chǎn)tmosphere

小題4:	A．fired B．fell C．opened D．floated

小題5:	A．heavily B．softly C．suddenly D．immediately

小題6:	A．A computer B．A rocket C．A pilot D．An astronaut

小題7:	A．spread B．traveled C．shot D．moved

小題8:	A．far B．long C．distant D．a(chǎn)way

小題9:	A．shouted B．watched C．cheered D．welcomed

小題10:

A．make B．take C．show D．search

小題11:

A．red B．brown C．gray D．black

小題12:

A．careful B．close C．real D．clear

小題13:

A．men B．life C．trees D．a(chǎn)ir

小題14:

A．parts B．rockets C．engines D．centers

小題15:

A．through B．towards C．over D．a(chǎn)round

小題16:

A．enter B．examine C．collect D．discover

小題17:

A．orbiter B．lander C．spaceship D．rocket

小題18:

A．engineers B．a(chǎn)stronauts C．parachutes D．instruments

小題19:

A．surface B．trees C．rocks D．pictures

小題20:

A．spaceship B．rocket C．lander D．information

One night in March 1999, a man was driving from California to Oregon, US, to visit some friends. He had stopped his car to have some food when he started to hear strange noises. Turning on the headlights, he saw an 8-foot-tall creature covered in thick, dark hair. The creature stared at him for a minute, turned in the road and walked off slowly into the woods.

In the past 50 years alone, there have been thousands of reported sightings of similar creatures in the US, Canada, the Himalayas(喜馬拉雅山地區(qū))and even Hubei Province in China. The creature is known as bigfoot.
Bigfoot is said to be a very tall(between 2 and 4. 5 metres), ape-like(類人猿似的)creature that is covered in hair and walks upright on two legs. It is very wary(警惕的)of human beings.
Believers think bigfoot is a direct descendent(后代)of ancient gigantopithecus(巨猿). But it remains one of the planet’s undiscovered secrets. There is a little evidence(證據(jù))to support the believers’ theory: traces of hair, footprints and body prints as well as the reported sightings. Some people have even showed what they say with photos or films of bigfoot.
But so far, no one has found bones or any other definite proof that the giant creature exists.
As a result many people believe the evidence is just part of a big trick.
The footprints are easy to make and they say: all you need to do is to make two large feet out of plaster(石膏), attach them to the bottom of your shoes and walk with big steps. As for the photos and films, they are just people dressed in ape suits.
They also say the sightings are not real, just people making mistakes. For example, bigfoot could be a bear living in the wild that sometimes stands up on its back legs.
小題1: So far what we can be sure about is that　　　　.

A．there exist savages(野人)in several places in the world

B．there are some traces of hair, footprints and body prints of the “bigfoot”

C．bigfoot is a direct descendent of ancient gigantopithecus

D．a(chǎn)ll the big foot discovered have the same look

小題2:It was in　　　that man first found the ape-like creature.

A．1999	B．the 1960’s
C．the 1950’s	D．the 1940’s

小題3: The article infers but doesn’t say so that some people　　　　bigfoot’s existence.

A．may fool the world into believing

B．have definite evidences to prove

C．refuse to believe

D．will soon offer proofs of

小題4:If bigfoot is just a misunderstanding, what they saw might NOT be　　　　.

A．a(chǎn)pes

B．bears

C．gigantopithecus

D．people dressed in animal skins

You may be fascinated with pictures of animals in the wild. You might have imagined yourself taking pictures of animals that are rarely seen in the city. If you do get that chance, you may want to consider the following tips or rules.

First of all, a lot of professional photographers give respect to these animals and the environment they are in. Just remember that you should respect the animals and the environment in case these animals bite or hurt you.
Keep in mind that you are taking pictures of real, live, wild animals. A wild animal may bite to protect itself. You must be sensitive while taking their pictures and be gentle in all your movements. Do not feed the animals, or interact with animals that are sleeping or caring for their young.
If you are going to a place where it is privately(私人)owned, you’d better get the owner’s permission first before you start taking pictures.
Change the flash of your camera to natural light, so the animals will not be frightened or surprised when you start shooting. Animals do not react well when they are surprised.
Be very patient. Make sure you are aware of the changes in behavior of the animal and its moods. Be familiar with the animals’ natural habitat.
Now if those rules are clear, it is time for planning. Consider the weather; some animals do not go out when it is raining while some animals love the rain. Therefore, a little research on the weather will not hurt. You should consider taking pictures after sunrise and before sunset. Now if the animal is nocturnal(夜間活動(dòng)的), then you should prepare to battle not only the wild but also the darkness.
An adventure in the wild will make you very excited. However, you should be well equipped, have experts to back you up, and also a permit for doing the photo shoot. If you do not have any of these, then maybe you should consider visiting the zoo instead.
小題1:The main purpose of the author in writing this passage is　　　.

A．to call for us to protect animals

B．to show where to buy pictures of animals

C．to explain how to get along with wild animals

D．to give us tips on taking pictures of animals in the wild

小題2:Which of the following aspects is NOT mentioned in the passage?

A．Respecting the animals.

B．Making gentle movements.

C．Making the animals happy.

D．Changing the flash of your camera to natural light.

小題3: If the animals are on a farm owned by a person, we should　　　.

A．a(chǎn)sk the owner to take pictures for us

B．a(chǎn)sk for the owner’s permission first

C．make sure the owner is present when we take pictures

D．take pictures when the owner is feeding animals

小題4: We can infer from the passage that　　　.

A．most animals love being taken pictures of

B．we have to finish the pictures before sunset

C．we’d better take pictures when the animals are sleeping

D．we should pay attention to the animals’ moods when taking pictures

小題5:What preparation should you do before going to take pictures of wild animals?
①Preparing some food to feed the animals.
②Asking experts for advice.
③Knowing the weather in the animals’ habitat.
④Getting a permission for taking pictures of wild animals.

A．①②④

B．②③④

C．①②③

D．①③④