题目
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often allow them to walk again. Newts (蝾螈)in the same situation, on the other hand, can grow
limbs back on their own! Scientists have known for a long time that certain animals can regrow
limbs, but they haven"t quite figured out how these creatures do it.
Researchers have now come up with some new ideas. Their work may give people the ability
to regrow lost limbs. The researchers started with two simple experiments: when you cut a newt"s
leg at the ankle, only the foot grows back; when you cut off a leg at the very end, the whole leg
grows back. In both cases, the regrowth begins with stem cells. Stem cells can develop into nearly
any type of cell in the body.
How do a newt"s stem cells know when to grow only a foot and when to regrow a whole leg?
This question relates to another mystery. In newt"s, a cutoff leg will grow back only if the nerve
bundle(神经束) in it also grows back, but if something prevents the nerve bundle from growing the
stem cells at the wound won"t regrow a new leg.
In its study, a British team focused on a protein called nAG. When the team prevented nerves in
a limb from growing, but added the nAG protein to stem cells in the limb, the limb still regrew. That
protein seems to guide limb regrowth. People have proteins that are similar to nAG. Further research
into these materials may someday help human limbs recover by themselves.
B. its leg was cut off and the nerve bundle stopped growing
C. its leg was cut off and the nerve bundle could grow back
D. its ankle and the nerve bundle could grow back
B. Proteins similar to nAG.
C. Stem cells and proteins.
D. Stem cells and nerve bundles.
B. shows where researchers got their new ideas
C. states the author"s opinion
D. describes the result of researchers" studies
B. To find out the similarity between human and newts.
C. To find out what is nAG.
D. To find a way of helping human limbs recover by themselves.
答案
核心考点
试题【阅读理解。 When people lose legs after accidents or illnesses, emergency care an】;主要考察你对题材分类等知识点的理解。[详细]
举一反三
surprise. The car is fitted with a remote immobiliser (锁止器), and a radio signal from a control centre
miles away will ensure that once the thief switches the engine off, he will not be able to start it again.
The idea goes like this. A control box fitted to the car contains a mini-cellphone, a micro-processor
and memory, and a GPS (全球定位系统) satellite positioning receiver. If the car is stolen, a coded
cellphone signal will tell the control centre to block the vehicle"s engine management system and prevent
the engine being restarted.
In the UK, a set of technical fixes is already making life harder for car thieves. "The pattern of vehicle
crime has changed," says Martyn Randall, a security expert. He says it would only take him a few minutes
to teach a person how to steal a car, using a bare minimum of tools. But only if the car is more than 10
years old.
Modern cars are far tougher to steal, as their engine management computer won"t allow them to start
unless they receive a unique ID code beamed out by the ignition (点火) key. In the UK, technologies
like this have helped achieve a 31% drop in vehicle-related crime since 1997.
But determined criminals are still managing to find other ways to steal cars, often by getting bold of
the owner"s keys. And key theft is responsible for 40% of the thefts of vehicles fitted with a tracking
system.
If the car travels 100 metres without the driver confirming their ID, the system will send a signal to
an operations centre that it has been stolen. The hundred metres minimum avoids false alarms due to
inaccuracies in the GPS signal.
Staff at the centre will then contact the owner to confirm that the car really is missing, and keep police
informed of the vehicle"s movements via the car"s GPS unit.
B. To allow the car to lock automatically when stolen.
C. To prevent the car thief from restarting it once it stops.
D. To prevent car theft by sending a radio signal to the car owner.
suggests that ________.
B. self-prepared tools are no longer enough for car theft
C. the thief has to make use of computer technology
D. the thief has lost interest in stealing cars over 10 years old
B. A unique ID card.
C. A special cellphone signal.
D. A GPS satellite positioning receiver.
centre?
B. To keep police informed of the car"s movements.
C. To give the driver time to contact the operations centre.
D. To allow for possible errors in the GPS system.
B. Contact the car owner.
C. Block the car engine.
D. Locate the missing car.
scientists were overjoyed with the chance to examine the remains of the past. The ship construction
showed how ships were built and operated during the seventeenth century. In this way, artifacts,
objects made by human beings, provided a picture of daily life almost 400 years ago.
Underwater archaeology-the study of ships, aircrafts(工艺品) and human settlements that have sunk
under large bodies of water-is really a product of the last 50 years. The rapid growth of this new area
of study has occurred because of the invention of better diving equipment. Besides the Swedish ship
wreck(残骸),underwater archaeologists have made more exciting discoveries such as the
5000-year-old boats in the Mediterranean Sea.
Underwater archaeology can provide facts about the past. In ancient ports all over the world are
ships sunken in the past 6,000 years. There are also sunken settlements in seas and lakes telling of
people"s way of life and their systems of trade in ancient times.
Underwater archaeologists want to study these objects to add to the world"s knowledge of history,
but they have to fight two enemies. One enemy is treasure hunters who dive for ancient artifacts that
they can sell to collectors. Once sold, these objects are lost to experts. The second enemy is dredging
machines(挖掘机)often used to repair ports. These machines destroy wrecks and artifacts or bury
them deeper under sand and mud. By teaching the public about the importance of underwater
"museums" of the past, archaeologists are hoping to get support for laws to protect underwater treasures.
B. To attract readers" attention to the topic
C. To use an example to support the topic
D. To offer basic knowledge of the topic
B. search for underwater life
C. study underwater artifacts
D. examine underwater environment
B. their knowledge of world history is limited
C. dredging machines cause damage to the ports
D. sold artifacts can hardly be regained for research
B. To discuss the scientists" problems.
C. To explain people"s way of life in the past.
D. To describe the sunken ships.
foods: change their memories. Scientist Elizabeth Loftus of the University of California at Irvine asked
volunteers to answer some questions on their personalities and food experiences. "One week later,"
Loftus says, "we told those people we"d fed their answers into our smart computer and it came up with
an account of their early childhood experiences." Some accounts included one key additional detail.
"You got sick after eating strawberry ice-cream." The researchers then changed this detail into a
manufactured (人为促成的) memory through leading questions -Who were you with? How did you
feel? By the end of the study, up to 41% of those given a false memory believed strawberry ice-cream
once made them sick, and many said they"d avoid eating it.
When Loftus published her findings, she started getting calls from people begging her to make them
remember hating chocolate or French fries. Unfortunately, it"s not that easy. False memories appear to
work only for foods you don"t eat on a regular basis. But most importantly, it is likely that false memories
can be implanted (灌输) only in people who are unaware of the mental control. And lying to a patient is
immoral(不道德的), even if a doctor believes it"s for the patient"s benefit.
Loftus says there"s nothing to stop parents from trying it with their overweight children. "I say, wake
up -parents have been lying about Father Christmas for years, and nobody seems to mind. If they can
prevent diseases caused by fatness and all the other problems that come with that, you might think that"s
more moral lie. Decide that for yourself."
B. To find out details she can make use of.
C. To find out their attitudes towards food.
D. To predict what food they"ll like in the future.
B. People tend to forget their childhood experiences.
C. People can be led to believe in something false.
D. People are not always aware of their personalities.
B. learn it is harmful for health
C. lie to themselves that they don"t want it
D. are willing to let doctors control their minds
B. When it is effective.
C. How it should be used.
D. Whether it is moral.
accused of wasting money on art and decoration as it suggests a pleasant environment helps patients
ease discomfort and pain.
A team headed by Professor Marina de Tommaso at the Neurophysiopathology Pain Unit asked
a group of men and women to pick the 20 paintings they considered most ugly and most beautiful
from a selection of 300 works by artists such as Leonardo da Vinci and Sandro Botticelli. They
were then asked to look at either the beautiful paintings, or the ugly painting, or a blank panel(板)
while the team put a short laser pulse at their hand, creating a sensation as if they had been stuck
by a pin. The subjects rated the pain as being a third less intense(剧烈的) while they were viewing
the beautiful paintings, compared with when looking at the ugly paintings or the blank panel.
Electrodes(电极) measuring the brain"s electrical activity also confirmed a reduced response to the
pain when the subject looked at beautiful paintings.
While distractions, such as music, are known to reduce pain in hospital patients, Prof de Tommaso
says this is the first result to show that beauty plays a part.
The findings, reported in New Scientist, also go a long way to show that beautiful surroundings could
aid the healing process.
"Hospitals have been designed to be functional, but we think that their artistic aspects should be
taken into account too," said the neurologist. "Beauty obviously offers a distraction that ugly paintings
do not. But at least there is no suggestion that ugly surroundings make the pain worse. I think these
results show that more research is needed into the field how a beautiful environment can alleviate
suffering."
Pictures they liked included Starry Night by Vincent Van Gogh and Botticellis Birth of Venus.
Pictures they found ugly included works by Pablo Picasso, the Italian 20th century artist Anonio
Bueno and Columbian Fernando Botero. "These people were not art experts so some of the
pictures they found ugly would be considered masterpieces by the art world," said Prof de Tommaso.
B. relieve
C. improve
D. kill
B. Hospitals must take their artistic aspects into consideration first.
C. Ugly surroundings will surely make the pain worse.
D. Both music and beauty can reduce pain in hospital patients.
B. only art experts could judge they were masterpieces or not, though ugly
C. the artists mentioned above were not really art masters.
D. some of them were art masters, while others were not.
B. Ugly paintings could be masterpieces.
C. More research should be done in the field.
D. Latest environmental research.
As we all know, games play a very important role in the growth of children. Children should grow
along with playing games, for, _1 playing games, they can not only acquire knowledge, but also
cultivate their abilities to get along with others.
However, most children _ 2 (face) with a completely different situation. Most parents fear that
games will prevent children from increasing new knowledge and 3_ the children will fail in the future
examinations. So, instead of _4_ ( let ) the children 5 find and learn naturally from their surroundings,
they force their children to take part in various kinds of classes, learning English, playing 6 piano or
practicing drawing, etc. What"s more, some parents put 7 the children"s toys which are very useful
in developing children"s imagination and practical abilities.
8 is a piece of good advice to those parents: 9 you want to expect your child to be able to
accomplish something, you must first of all develop his ability to adapt to the new surroundings. That
cram education can lead to nothing _10 a failure in the children"s growth.
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