A
(2020·马鞍山质量预测)
If you’ve ever had a dog, you know just how deep a connection you can develop with “man’s best friend”. But a dog’s life is much shorter than humans, about 12 to 15 years long, which means every dog owner has to go through the heartbreaking moment when their loving pet passes away.
Why not make a clone of that dog then? This is the solution offered by a South Korean company, Sooam Biotech Research Foundation. The company has already successfully cloned at least 400 dogs, mostly for US customers, ever since it pioneered the technique in 2005. Now, Sooam Biotech has introduced its business to UK dog owners as well, offering them dogs that look just like their lost ones.
To clone a dog, researchers first need to take a skin cell from a living dog or one that has just died. Meanwhile, another dog is selected to supply an egg. Researchers then replace the DNA in the egg with that from the skin cell and implant the egg into the womb(子宫) of a female dog. The egg grows into a puppy over the following two months.
The whole process takes a very short time, but it comes at a shockingly high price—around £ 63,000. But if you can’t afford it now, you can also save the cell in a laboratory and access it at a later date.
However, magical as cloning might sound, there is no guarantee that the cloned dog will be a perfect copy of the original one. Just like identical twins of humans, they share the exactly same DNA but there will still be small differences between them. “The spots on a Dalmatian(斑点狗) clone will be different, for example,” Insung Hwang, head of Sooam Biotech, told The Guardian.
Dog owners will also have to accept the fact that personality is not “cloneable”. Apart from genes, personality is also determined by upbringing and environment, which are both random elements that cloning technologies simply cannot overcome, Professor Tom Kirkwood at Newcastle University, UK, told The Telegraph.
Perhaps bringing our dogs back by cloning is not the best way to remember them after all. Kirkwood, a dog owner himself, pointed out, “An important aspect of our relationship with them is coming to terms with the pain of letting go.”
【解题导语】 本文是一篇说明文,主要介绍了克隆狗技术。
1.What service does Sooam Biotech Research Foundation offer?
A.Making copies of pet dogs.
B.Giving pet dogs identical twins.
C.Helping dogs give birth to more puppies.
D.Helping dog owners love their dogs more.
A 解析:细节理解题。根据第二段最后一句“Now, Sooam Biotech has introduced its business to UK dog owners as well, offering them dogs that look just like their lost ones.”可知,这家公司所提供的服务就是克隆已逝的宠物狗,故选A。
2.Which order is correct in the dog cloning process?
a.An egg is taken from another dog.
b.A skin cell is taken from the pet dog.
c.The egg grows into a puppy in two months.
d.The egg is placed in the womb of a female dog.
e.The DNA in the egg is replaced by the DNA from the skin cell.
A.a→d→b→e→c. B.a→e→b→d→c.
C.b→a→d→e→c. D.b→a→e→d→c.
D 解析:细节理解题。根据对第三段的整体理解可知,实验的第一步是从狗身上提取皮肤细胞,另一只被选择的狗提供一个卵子,将卵子中的DNA替换成皮肤细胞中的DNA之后,将卵子植入一只母狗的子宫,最后卵子在接下来的两个月中生长为一只小狗,故选D。
3.What can we learn about dog cloning from the passage?
A.It has not been put into practice until recently.
B.It is very popular among US and UK pet owners.
C.It might not give the owners an exactly same dog.
D.It is very expensive and usually takes half a year to complete.
C 解析:细节理解题。根据第五段第一句“However, magical as cloning might sound, there is no guarantee that the cloned dog will be a perfect copy of the original one.”可知,克隆狗和原来的狗可能并非完全一样,故选 C。
4.What does Kirkwood think of dog cloning?
A.He disagrees with it.
B.He supports it.
C.He is curious about it.
D.He thinks it unbelievable.
A 解析:观点态度题。根据最后一段Kirkwood说的话“An important aspect of our relationship with them is coming to terms with the pain of letting go.”可知,他认为人类和宠物狗之间的关系的一个重要方面是要接受失去它们的痛苦。由此可推知,Kirkwood并不赞成克隆狗,故选A。