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     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, 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, 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 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 the embryo into a host animal.

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

　　“The nuclear transfer 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 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.”

　　1. The aim of “Noah’s Ark” project is 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 nuclear of one animal to another

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

　　A. available panda eggs   B. host animals

　　C. qualified researchers   D. enough money

　　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

　　4. From the passage we know that _______.

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

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

　　C. Kraemer will work with Chinese scientists in clone researches

　　D. about two thousand of species will probably die out in a century

background information

　動物體細胞克隆技術又稱體細胞核移植技術或無性繁殖技術，它是用動物特定發育階段的核供體（體細胞核）及相應的核受體（去核的原核胚或成熟的卵母細胞、卵細胞）不經過有性繁殖過程，進行體外重構，并通過重構胚的胚胎移植，從而達到擴繁同基因型動物種群的目的。

    體細胞克隆的類型2種，一種是同種體細胞核移植，科學家用取自一只6歲成羊的乳腺細胞培育成功一只克隆羊，開創了成年哺乳動物克隆的先河。第二種是異種體細胞核移植，陳大元等將大熊貓的子宮上皮細胞、骨骼肌細胞和乳腺上皮細胞的細胞核移入去核的兔卵母細胞后，分別有9.9 %、6.8 % 和11.7 %的重構卵發育到囊胚，染色體、線粒體DNA和核DNA分析均證實異種重構胚的核遺傳物質來自大熊貓供體細胞。這不僅開創了大熊貓體細胞移核的先例，而且首次大熊貓體細胞核的異種移核。對大熊貓的快繁及保護提供了一線希望。

vocabulary

　embryo胚胎

endangered species瀕危物種

nitrogen氮

groundbreaking 開拓性的=innovative

clone克隆

【答案解析】

　　本文講述中國正在竭力克隆瀕臨絕種的熊貓，這和Texas A & M University 的Noah's Ark(諾亞方舟)工程極為相似，都是想拯救瀕臨滅絕的動物。

　　1. B。語義理解題。從第2段內容可知，“諾亞方舟”工程的目標是把瀕臨滅絕的動物的蛋(卵)、胚胎、精液和DNA儲存在液體氮中，如果某一種動物瀕臨滅絕時，將來可以重現這一動物。

　　2. A。細節題。從第6段第1句話 The nuclear 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  可以做出正確判斷。

　　3. C。主旨題。從文章內容來看，無論是中國還是世界克隆熊貓還沒有成功，所以排除A、B項；D項內容明顯與文章內容不符，故排除。所以“探索克隆熊貓的可能性”應該是這篇文章的標題。

　　4. D。判斷題。此題B項的干擾性較強，但由于它沒有說明是Chinese scientists，所以應排除。A、C項明顯與原文不符。根據文章第3段第1句可知答案非D莫屬。