题目内容

"Salty" Rice Plant Boosts Harvests
British scientists are breeding a new generation of rice plants that will be able to grow in soil containing salt water. Their work may enable abandoned farms to become productive once more.
Tim Flowers and Tony Yeo, from Sussex University's School of Biological Sciences,have spent several years researching how crops, such as rice, could be made to grow in,water that has become salty.
The pair have recently begun a three-year programme, funded by the Biotechnology and Biological sciences Research Council, to establish which genes enable some plants to survive salty conditions. The aim is to breed this capability into crops, starting with rice.
It is estimated that each year more than 10m hectares (公顷) of agricultural land are lost because salt gets into the soil and stunts (妨碍生长) plants. The problem is caused
by several factors. In the tropics, mangroves (红树林) that create swamps (沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep (渗透) in. In Latin America, irrigation often causes problems when water is evaporated (蒸发) by the neat, leaving salt deposits behind.
Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up .the water they need to survive.
To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do not affect the plants'
,growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resulting seeds are ready to be considered for commercial use.
Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world.
第 31 题 Which of the following statements about Flowers and Yeo is true.

A. They are students at Sussex University.
B. They are rice breeders.
C. They'are husband and wife.
D. They are colleagues at an institution of higher learning.

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更多问题

What was scientists’ understanding of cryptic species?

A. They occurred in equal numbers in all biogeographical regions.
B. They were mostly found in insects and reptiles.
C. They were likely to be in tropical rather than temperate regions.
D. Both B and C.

According to Paragraph 4,what does Rome plan to do?

A. To make the backpack more comfortable for the wearer.
B. To put the backpack on the market.
C. To test the advantage of the backpack.
D. To promote the backpack in a newspaper 0r 0n television.

Crashed Cars to Text Message for Help
There is no good place to have a car crash—but some places are worse than others.In a foreign country,for instance,______(1)to explain via cell-phone that you are upside down in a ditch when you cannot speak the local language can fatally delay the arrival of the emergency services.
But an answer may he at hand.Researchers funded by the European Commissiono are beginning tests of a system called E-merge that______(2)senses when a car has crashed and sends a text message'telling emergency services。 in the local language that the accident has taken place.
The system was______(3) by ERTIC0,a transport research organization based in Brussels,Belgium.Cars are fitted with a cell-phone-sized device attached______(4)the underside of the dashboard which is activated by the same sensor that triggers the airbag in a crash.The device______(5)a cell-phone circuit,a GPS positioning unit and a microphone and loudspeaker.
It registers the severity of the crash by______(6)the deceleration data from the airbag's sensor.Using GPS information,it works out which country the Car is in,and from this it determines (7)which language to compose an alert message detailing precise location of the accident.
The device then automatically makes a call to the local emergency services______(8).If the car's occupants are conscious,they can communicate with the operator______(9)the speaker and microphone.
E-merge also transmits the vehicles make,model,color and license number,amt its heading when it crashed,which in rum indicates on which side of a multi-1ane highway it ended up.
This______(10)the emergency services find the vehicle as soon as they arrive on the scene.
“We can waste a large______(11)time searching for an incident,”says Jim Hammond,a(an)______(12)in vehicle technology at the Association of Chief Police Officers in the UK.Tests will begin soon with police car fleets in the UK.Trials have already started in Germany,Sweden,Spain,the Netherlands and Italy.
In-car systems…that summon the emergency services after a(:rash have______(13)been fitted in some premium cars “ERTICO says that______(14)EU states” are willing to fund the necessary infrastructure,E-merge could be working by,2008.
A study by French car maker Renault” concluded that the system could save up to 6000 of the 40.000 lives lost each year on Europe’ S roads.and prevent a similar number of serious injuries.
The Renault study estimates that fitting E.merge to every car in Europe would eventually save around 1 50 billion per______(15)in terms of reduced costs to health services and insurance companies,and fewer lost working days.
第 46 题

A. try
B. tried
C. trying
D. having tried

A.awkward B.crude C.I.eligiOUS D.foolish

A. awkward
B. crude
C. I.eligiOUS
D. foolish

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