题目要求:阅读下面的短文。短文后面有5个问题,每个问题有4个备选答案。请根据短文的内容选择正确的答案。
! y$ ~; @( w; s4 h6 ` Clone Farm* @, r7 s7 }" Z M5 e! }; m
Factory farming could soon enter a new era of mass production. Companies in the US are developing the technology needed to “clone” chickens on a massive scale. Once a chicken with desirable traits has been bred or genetically engineered, tens of thousands of eggs, which will hatch into identical copies, could roll off the production lines every hour. Billions of clones could be produced each year to supply chicken farms with birds that all grow at the same rate, have the same amount of meat and taste the same.
* q8 [0 w* @ d4 a e- A- x8 n! p This, at least, is the vision of the US’s National Institute of Science and Technology, which has given Origen Therapeutics of Burlingame, California, and Embrex of North Carolina $4.7 million to help fund research. The prospect has alarmed animal welfare groups, who fear it could increase the suffering of farm birds.6 M0 W1 q {" G7 [( K& s
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That’s unlikely to put off the poultry industry, however, which wants disease-resistant birds that grow faster on less food. “Producers would like the same meat quantity but to use reduced inputs to get there,” says Mike Fitzgerald of Origen. To meet this demand, Origen aims to “create an animal that is effectively a clone”, he says. Normal cloning doesn’t work in birds because eggs can’t be removed and implanted. Instead, the company is trying to bulk-grow embryonic stem cells taken from fertilized eggs as soon as they’re laid. “The trick is to culture the cells without them starting to distinguish, so they remain pluripotent,” says Fitzgerald./ B4 c$ t9 ]3 v0 B" l4 x" u7 ]3 L
Using a long-established technique, these donor cells will then be injected into the embryo of a freshly laid, fertilized recipient egg, forming a chick that is a “chimera”. Strictly speaking a chimera isn’t a clone, because it contains cells from both donor and recipient. But Fitzgerald says it will be enough if, say, 95 percent of a chicken’s body develops from donor cells/ “In the poultry world, it doesn’t matter if it’s not 100 percent,” he says.
" Y- a; a! w: e Another challenger for Origen is to scale up production. To do this, it has teamed up with Embrex, which produces machines that can inject vaccines into up to 50,000 eggs an hour. Embrex is now trying to modify the machines to locate the embryo and inject the cells into precisely the right spot without killing it.: Z: m+ g+ R- r6 b7 E
In future, Origen imagines freezing stem cells from different strains of chicken. If orders come in for a particular strain, millions of eggs could be produced in months or even weeks. At present, maintaining all the varieties the market might call for is too expensive for breeders, and it takes years to bread enough chickens to produce the billions of eggs that farmers need.' u& b9 S' W. h) @/ t3 f+ W1 U) H
练习:1 o; _1 V( Y6 ^4 K# `+ [: v
1. Which statement is the best description of the new era of factory farming according to the first paragraph?% R1 i% `, r! t% p& }
A eggs are all genetically engineered.
9 H4 I" J) N0 ?# F# R1 G* w B thousands of eggs are produced every hour.! ~, T3 ]. m& U' i
C cloned chicken are bulk-produced with the same growth rate, weight and taste.
5 f# |4 ?1 k* B6 f D identical eggs can be hatched on the production lines.
+ I& a X. h8 K9 K0 N 2. Which institution has offered $4.7 million to fund the research?+ u- P9 Q; K' A! L
A the US’s National Institute of Science and Technology.: x. L0 M+ h# D
B Origen Therapeutics of Burlingame, Carfornia.
$ @7 s! s' x2 J+ E. E& E C Embrex of North Carolina
3 d& y. q: Z/ d- ~- B" O D animal welfare groups.
6 Z5 W8 _; R# ~* ] 3. In the third paragraph, by saving “producers would like the same meant quantity but to use reduced inputs to get there,” Mike Fitzgerald means that he wishes." g. A! s9 }) T' _9 n7 O
A chickens’ quality could be maintained but with less investment.
% m$ K4 v } f# x; X9 _# A' @ B chickens’ taste could be improved but at less costs.3 v1 O) n4 B5 j, ^6 p
C chickens’ growth rate could be quickened but with less inputs.
- }. p/ s. [9 c r8 v' V' {) }3 @ D chickens’ could grow to the same weight but with less feed.8 C+ B" c2 k# ~+ m) ^ u
4. Which of the following statements about Origen and Embrex is correct according to the fifth paragraph?
/ `9 G' h2 ^# v3 s9 i8 P A origen and embrex will jointly invent machines to increase production.) v; |% J* r6 I) g3 o
B origen wants to purchase an efficient donor cells injectin machine.. u- V2 S1 j5 d& E7 @% I, H4 t
C origen has joined hands with exbrex in producing cell-locating machines.' K4 D' ]$ [' o
D origin is the leading company in producing embryo-locating machines.
$ D& N) G2 C: A% \) [) ]6 e6 b7 _+ z 5. The technology of freezing stem cells from different strains of chicken can do all the following EXCEPT that
- O4 L. a8 P% `$ h, K, m- J8 z1 @ A farmers can order certain strains of chicken only.- \( L1 f6 G$ i. Q
B origin can supply all the strains of chicken the market might need.* A `* c1 h2 R- {! i5 L
C chicken farmers order certain strains of chicken for economic reasons.
4 w/ I; ?& }5 |, W- q. y+ u D chicken farmers can be supplied with whatever strain they need.. I! w( L) g3 U$ M1 b9 y& M3 L- C. h
参考答案: C A D C A
* P- j: c9 B6 h7 s' V/ S 答案解析:+ _. v+ l9 g6 Q6 p0 Z) Y( N/ _
1 C 第一段最后一句提供了直接的答案。
) x* ^; q0 h1 L* P6 T 2 A 第二段共提到了三个研究机构和一个民间组织。The US’s National Institute of Science and Technology为研究提供了经费,被资助的研究机构是origen therapeutics of Burlingame, California 和 Embrex of north Carolina.因此,A 是答案。& G5 {1 Z: P4 }' Q- S0 A0 t# M+ F
3 D 原句的意思有两点是关键的,即每只鸡提供的肉量不变,但饲料要减少。只有D符合题意。
" v5 G$ [* t) Q: X 4 C 该段第二句中which引导的从句表明,是embrex生产疫苗注射装置,而不是两家研究单位共同研制。Embrex在此基础上将装置改造为细胞注射装置。所以,只有C最接近原意。
9 U# h. i- J- E: G& [1 ]9 r7 I5 ` 5 A 第六段的大意是,如果能冷冻所有品种的鸡的干细胞,那么,无论需要什么品种的鸡蛋或多少数量,都不是问题,但是,目前储备所有品种是非常昂贵的。B、C、D从几方面表达了这层意思。因此,只有A是答案。 |