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        2017職稱英語(yǔ)理工類A級(jí)閱讀理解模擬試卷(3)

        字號(hào):

        Clone Farm(克隆農(nóng)場(chǎng))
            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 scale1. Once a chicken with desirable traits has been bred or genetically engineered2, tens of thousands of eggs, which will hatch into identical copies3, 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.
            工業(yè)化農(nóng)場(chǎng)很快會(huì)進(jìn)入一個(gè)大產(chǎn)量的新領(lǐng)域。美國(guó)的公司正在開(kāi)發(fā)一項(xiàng)需要大規(guī)模克隆小雞的技術(shù)。一旦一個(gè)具有所期望特性的小雞被孵化出來(lái)或被基因改造,每小時(shí)成千上萬(wàn)的雞蛋會(huì)孵出如出一轍的小雞滾下生產(chǎn)線。每年上百萬(wàn)的克隆小雞能被孵化出來(lái),從而為雞場(chǎng)提供以相同比例生長(zhǎng),重量相同并且味道相同的小雞。
            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 research4. The prospect has alarmed animal welfare groups, who fear it could increase the suffering of farm birds.
            這至少是美國(guó)國(guó)家科技院的夢(mèng)想,科技院給OnrigenTherapeuticsofBurlinggame,California,以及EmbrexofNorthCaroling470萬(wàn)基金以資助研究。這個(gè)預(yù)想為擔(dān)憂增加雞場(chǎng)小雞痛苦的動(dòng)物福利組織拉響了警報(bào)。
            That's unlikely to put off5 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-grow6, embryonic stem cells7 taken from fertilized eggs as soon as they're laid. "The trick is to culture8 the cells without them starting to distinguish, so they remain pluripotent," says Fitzgerald.
            那好像并沒(méi)有讓使家禽養(yǎng)殖業(yè)氣餒,然而,他們想使抗痛小雞吃得更少,長(zhǎng)得更快,“養(yǎng)殖者希望減少投入但仍獲得相同的產(chǎn)量,”MikeFitzgeraldofOrigen說(shuō),為了達(dá)到這個(gè)要求,Origen致力于“制造一個(gè)有效克隆體的小雞,”他說(shuō),正常的克隆技術(shù)對(duì)鳥類無(wú)效,因?yàn)槁巡荒鼙灰苿?dòng)或移植。然而,公司正試圖大量繁殖剛產(chǎn)下的受精卵中提取的胚胎的干細(xì)胞。技巧是在細(xì)胞開(kāi)始顯示其差別前對(duì)其進(jìn)行培育,這樣它們還保持多能性?!盕itzgerald說(shuō)
            Using a long-established technique, these donor cells will then be injected into the embryo of a freshly laid, fertilized recipient egg9, 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.
            運(yùn)用早已形成的技術(shù),這些干細(xì)胞會(huì)被注入剛孵出的,已受精的,要接受細(xì)胞植入的雞蛋的胚胎中,形成一個(gè)嵌合體的小雞。嚴(yán)格地說(shuō),嵌合體的小雞不是克隆雞,因?yàn)樗扔兄踩氲募?xì)胞又有本身的細(xì)胞。但Fitzgerald說(shuō),如果小雞身體的95%是由被植入的細(xì)胞發(fā)展而來(lái)的就足夠了?!霸诩仪萁?,不是100%也沒(méi)關(guān)系?!?BR>    Another challenge for Origen is to scale up10 production. To do this, it has teamed up with11 Embrex, which produces machines that can inject vaccines into up to 50,000 eggs12 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.
            Origen面臨的另一個(gè)挑戰(zhàn)是提高生產(chǎn)量。為了做到這點(diǎn),他和Embrex合作研制了一個(gè)可將疫苗注入50000個(gè)雞蛋中的儀器。Embrex正試圖改造那個(gè)儀器,從而使胚胎和注射的細(xì)胞落在準(zhǔn)確的位置而不殺死它。
            In future, Origen imagines freezing stem cells from different strains of chicken13. 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 takes years to breed enough chickens to produce the billions of eggs that farmers need.
            在將來(lái),Origen設(shè)想將不同品種小雞的干細(xì)胞冷凍,如果定單要某一種小雞,成百萬(wàn)的卵能在幾個(gè)月甚至幾個(gè)星期被生產(chǎn)出來(lái),目前,維持市場(chǎng)可能需要的各種小雞對(duì)養(yǎng)殖者來(lái)說(shuō)太昂貴了,那要花數(shù)年的時(shí)間培育足夠多的小雞以生產(chǎn)出農(nóng)民需要的上百萬(wàn)雞蛋。
            詞匯:
            clone/klaun/n.&v.克隆,無(wú)性繁殖 implant /im丨pla:nt/ v.植入;移植 embryonic / 丨 embri 丨 mnk/ adj.胚胎的 fertilise /'f3:tilaiz/ v.使受精
            注釋:
            1. on a massive scale:大規(guī)模
            2. genetically engineered:經(jīng)過(guò)基因改造。genetical engineering:遺傳工程
            3. hatch into identical copies:孵出如出一轍的(小)雞
            4. to help fund research: 資助研究。fund用作動(dòng)詞,research是它的賓語(yǔ)。
            5. put off:意為 “discourage”(使……氣餒)。
            6. bulk-grow: 大量繁殖
            7. stem cell:干細(xì)胞
            8. culture:動(dòng)詞,意思是:培育。
            9. a freshly laid, fertilized recipient egg:新產(chǎn)下的;已受精的;要接受細(xì)胞植入的雞蛋
            10. scale up: 提高,按比例增加。
            11. team up with:與 合作。
            12. up to 50,000 eggs:多達(dá) 5 萬(wàn)只雞蛋。
            13. different strains of chicken:不同品種的雞。
            練習(xí):
            1. Which statement is the best description of the new era of factory farming according to the first paragraph?
            A. Eggs are all genetically engineered.
            B. Thousands of eggs are produced every hour.
            C. Cloned chickens are bulk-produced with the same growth rate, weight and taste.
            D. Identical eggs can be hatched on the production lines.
            2. Which institution has offered $4.7 million to fund the research?
            A. The US’s National Institute of Science and Technology.
            B. Origen therapeutics of Burlingame, California.
            C. Embrex of North Carolina.
            D. Animal welfare groups.
            3. In the third paragraph, by saying “Producers would like the same meat quantity but to use reduced inputs to get there.” Mike Fitzgerald means that he wishes
            A. chickens’ quality could be maintained but with less investment.
            B) chickens' taste could be improved but at less costs.
            C) chickens' growth rate could be quickened but with less inputs.
            D) chickens could grow to the same weight but with less feed.
            4. Which of the following statements about Origen and Embrex is correct according to the fifth paragraph?
            A) Origen and Embrex will jointly invent machines to increase production.
            B) Origen wants to purchase an efficient donor cells injecting machine.
            C) Origen has joined hands with Embrex in producing cell-injecting machines.
            D) Origen is the leading company in producing embryo-locating machines.
            5. The technology of freezing stem cells from different strains of chicken can do all the following EXCEPT that
            A) farmers can order certain strains of chicken only.
            B) Origen can supply all the strains of chicken the market might need.
            C) chicken farmers order certain strains of chicken for economic reasons.
            D) chicken farmers can be supplied with whatever strain they need.
            答案與題解:
            1. c 第一段最后一句提供了直接的答案。
            2. A 第二段共提到三個(gè)研究機(jī)構(gòu)和一個(gè)民間組織。The US's National Institute of Science and Technology為研究提供了經(jīng)費(fèi),被資助的研究機(jī)構(gòu)是Origen Therapeutics of Burlingame, California 禾口 Embrex of North Carolina.因此,A 是答案。
            3. D 原句的意思有兩點(diǎn)是關(guān)鍵的,即每只雞提供的肉量不變,但飼料(inputs)要減 少。只有D符合原意。
            4. C 該段第二個(gè)句子中which引導(dǎo)的從句表明,是Embrex生產(chǎn)疫苗注射裝置,而 不是兩家研究單位共同研制。Embrex在此基礎(chǔ)上將裝置改造為細(xì)胞注射裝置。所以, 只有C最接近原意。
            5. A 最后一段的大意是,如果能冷凍所有品種的雞的干細(xì)胞,那么,無(wú)論需要什么 品種的雞或多少數(shù)量,都不是問(wèn)題。但是,目前儲(chǔ)備所有品種是非常昂貴的。B、C、 D從幾方面表達(dá)了這層意思。因此,只有A是答案。