阅读理解:
Clone Farm
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. Thats 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 doesnt work in birds because eggs cant be removed and implanted, Instead, the company is trying to bulk-grow embryonic stem cells taken from fertilized eggs as soon as theyre laid. The trick is to culture the cells without them starting to distinguish, so they remain pluripotent, says Fitzgerald.
Another challenge 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.
41.Which statement is the best description of the new era of factory farming according to the first paragraph?
B. Thousands of eggs are produced every hour.
D. Identical eggs can be hatched on the production lines.
A. The USs National Institute of Science and Technology.
C. Embrex of North Carolina.
43. 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
B. chickens taste could be improved but at less costs.
D. chickens could grow to the same weight but with less feed.
A. Origen and Embrex will jointly invent machines to increase production.
C. Origen has joined hands with Embrex in producing cell-injecting machines.
45. The technology of freezing stem cells from different strains of chicken can do all the following EXCEPT that
B. Origen can supply all the strains of chicken the market might need.
D. chicken farmers can be supplied with whatever strain they need.
[形容词和副词]和more有关的词组
[特殊词精讲]be interested doing/to do
[形容词和副词]the + 最高级 + 比较范围
[动词]助动词be的用法
[动词不定式]不定式作宾语
[冠词和数词]冠词与形容词+名词结构
[代词]并列人称代词的排列顺序
[动词不定式]动名词与不定式
[特殊词精讲]remember doing/to do
[特殊词精讲]begin(start) doing/to do
[动词的时态]用现在进行时表示将来
[动名词]短语动词
[动词不定式]不定式的特殊句型too…to…
[动词不定式]用作介词的to
[特殊词精讲]go on doing/to do
[分词]分词
[动词]短语动词
[形容词和副词]以-ly结尾的形容词
[动词不定式]动词不定式
[形容词和副词]兼有两种形式的副词
[动词]非谓语动词
[特殊词精讲]regret doing/to do
[特殊词精讲]stop doing/to do
[代词]相互代词
[动词不定式]不定式的特殊句型so as to
[动词]助动词do 的用法
[特殊词精讲]try doing/to do
[独立主格]with的复合结构作独立主格
[动名词]动名词作主语、宾语和表语
[特殊词精讲]感官动词 + doing/to do
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