Ⅰ.阅读理解
Have you seen Jurassic Park? In this film, scientists use DNA kept for tens of millions of years to clone dinosaurs. They find trouble，however，when they realize that the cloned creatures are smarter and more dangerous than expected. That's nothing more than a fiction.
But could we really clone endangered animals?
To date, the most successful attempt to do so was the cloning of a gaur，a rare oxlike animal from southeast Asia. Scientists used a cow to bring the cloned baby gaur, named Noah. Two days after birth，however，Noah died from a common bacterial infection.Other endangered species that may be cloned include the African bongo antelope(羚羊), the Sumatran tiger, the cheetah(猎豹), and the giant panda.
Next，could we really clone extinct animals?
In theory？Yes.To do this, you need a wellkept source of DNA from the extinct animals such as wool mammoth(毛象)，Tasmanian tiger，or even dinosaur, and a closely related species, still living，which could serve as a_surrogate_mother.
In reality? Probably not. On the one hand, it's not likely that extinct animals' DNA could survive undamaged for such a long time. Cloning such extinct animals as wool mammoth, Tasmanian tiger，or dinosaur is much more difficult due to the lack of properly wellpreserved DNA. On the other hand, for example, a gaur can have a cow as a surrogate mother, definitely not a monkey. But what about an extinct animal as unique as the panda? What species could possibly serve as a surrogate mother?
Cloning presents many exciting possibilities.However, even if extinct animals were brought back，they could not survive in today's world. Not only do most extinct animals have no habitat to live in, but the other plants and animals they depended on for food may also be gone as well.
本文说明了在克隆灭绝动物的过程中遇到的种种困难与障碍。即使克隆成功了，其赖以生存的食物链也已经被破坏，被克隆出来的动物也无法继续走下去。
1．It can be learned from the text that ________.
A．the gaur is an extinct species
B．the gaur lives in Asia and is endangered
C．scientists have cloned the African bongo antelope
D．both the cheetah and the giant panda live in Asia
答案：B
解析：细节理解题。根据第二、三段可知，印度野牛生活在亚洲的东南部，濒临灭绝。
2．The underlined words “a surrogate mother” probably refer to a female who ________.
A．gives birth to a baby of its own
B．cannot give birth to a baby
C．gives birth to a baby for another female
D．provides DNA
答案：C
解析：词义猜测题。根据第五段的描述可知，此处表示的是，把一种动物的DNA提取出来之后，在另外一种动物的体内进行胚胎繁殖，而这种动物就被称为a surrogate mother，由此判断，画线部分意思为“代孕妈妈”，故C项正确。
3．The difficulty in cloning an extinct species is the lack of ________.
A．both the wellpreserved DNA and a surrogate mother
B．both the habitat to live in and the wellpreserved DNA
C．both the wellpreserved DNA and plants to live on
D．both the habitat to live in and plants to live on
答案：A
解析：细节理解题。根据文章倒数第二段中的“On the one hand...On the other hand...”两个方面的表述可知，克隆的困难在于一是要寻找灭绝动物的保存完好的DNA，二是要寻找到合适的代孕的物种，故A项正确。
4．In the author's opinion, it is possible that ________.
A．all the extinct species may be cloned
B．extinct species may be cloned and easily survive
C．a gaur can have a monkey as a surrogate mother
D．some extinct species may be cloned, but not survive
答案：D
解析：细节理解题。根据最后一段的表述可知，也许克隆存在众多的可能性，但是即使克隆成功了，也许会由于其赖以生存的食物链已经被破坏而无法继续存活下去。由此判断D项正确。
