68. There are more than two thousand species of plants    .

A. that exist only in this area           B. that will be harmed by the changing weather

C. that will survive in this area       D. that will die out in future

答案  65.D  66.A  67.C  68.A

Passage 4

(安徽省马鞍山二中2009届高三第四次模拟考试D篇)

With only about 1, 000 pandas left in the world, China is desperately trying to clone the animal and save the endangered species. That’s a move similar to what a Texas A & M University researchers have been undertaking for the past five years in a project called “Noah’s Ark”.

Noah’s Ark is 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(灭绝), Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.

It is estimated that as many as 2, 000 species of mammals, birds and reptiles will become extinct in over 100 years. The panda, native only to China, is 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 are now trying to implant(移植) the embryo into a host animal.

The entire procedure(程序) could take from three to five years to complete.

“The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available panda eggs could be a major problem,” Kraemer believes. “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,” adds Kraemer, who is 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.”

62. What is the purpose of the author in writing this passage?

A. Legs become weaker.

B. Modern means of transportation make the world a small place.

C. There is no need to use eyes.

D. The best way to travel is on foot.

答案  59.A  60.A  61.C  62.D

Passage 3

(安徽省马鞍山二中2009届高三第四次模拟考试C篇)

Scientists say California's special landscapes are changing gradually as the world gets warmer. Now, with a new generation of computer models, they're trying to make clear what those changes will be: Less snow?  More wildfires?  Fewer animals?

The new computer models allow scientists to divide the state into much smaller regions than ever before------just thirty-six square miles. These regional models give scientists a way of draping climate over California's complex landscape.    

Scientists want to understand how warming will affect the state's people, its economy, and the thousands of species that only live in California. The State's Climate Action Team has organized a meeting last month in Los Angeles on the economic effects of these targets.

California started the only state-run climate research program three years ago and is spending about$5 million a year on it. The goal of the research is to limit the impact of such changes.                                                                

California is part of an internationally recognized "hot spot" of biodiversity that extends north across the Oregon border and south into Baja California. It's home to 4,426 species of plants, nearly half of which are found nowhere else.

What happens in California could have broad influence. If California were a nation, it would be the fifth-biggest economy in the world and the 12th-biggest generator of greenhouse gases.   

Scientists are also looking beyond the greenhouse effect. For instance, urban development warms climate; cities give off more heat than natural areas. Cities also absorb more heat from the sun. This phenomenon is known as the "urban heat island effect". 

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