As if there weren’t enough of them in the world already, scientists have succeeded in cloning flies. The alike fruit flies are the first insects ever cloned, says the Canadian team that created them. The question everyone asks is why anyone would want to clone flies in the first place. She hopes that the insects , which are very easy to experiment with , will help to adjust the cloning process in other animals and even in humans, where the technique is being researched to aid production of therapeutic (治療的) stem cells.
In cloning, the DNA-containing nucleus of an adult cell is injected into an egg whose own nucleus(細(xì)胞核) has been removed. At the moment, the majority of cloned mice, sheep and other animals die before birth. It is thought this is because the adult DNA is not properly ‘reprogrammed’.
Using flies, researchers might discover genes that are important for this reprogramming, and that have matches in other animals. That is because it is relatively easy in flies to knock out the function of a single gene and then attempt cloning with these cells, which will test whether that gene is important. If such genes are confirmed, then in theory cloned mammalian embryos(晶胚) might be grown in selected solutions that change the activity of those genes to improve the technique’s success rate. Although some groups have attempted to clone insects before, Lloyd says this is the first time it has been successful. The team used a slight difference on the standard cloning process: they transferred nuclei taken from embryos rather than fully-grown adult cells. They sucked several nuclei (pl)out of developing fly embryos, and injected them into a fertilized(已受精的) fly egg. From over 800 early attempts, they cloned five adult insects, the group reports in the journal Genetics.
【小題1】The best title of this passage probably is _______.
A.The importance of clone |
B.First insects are cloned |
C.The disagreement in clone |
D.The advantages of clone |
A.there are fewer and fewer flies in the world |
B.flies are easy to find and cheap to use |
C.they can gain some experience before cloning other animals |
D.it is safe to clone flies |
A.the difference of other animals’ genes |
B.the improper technique of clone |
C.the complex of other animals |
D.the improper rearrange of the adult gene |
A.the clone of insects before used grown-up cells |
B.the clone of insects were never experimented before |
C.this time scientists cloned flies successfully and easily |
D.based on this success, other animals will be cloned in large quantities. |
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US musician and poct Gil Scott-Heron, often called the Godfather of Rap, has died in a New York hospital 62. 1
Scott-Heron was born in Chicago in 1949-the son of a former Britain football player. 2
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3 But the artist himself refused this title.“If ther was any individual initiative that I was responsible for, it might have been that there was music in certain poems of mine, with complete progression and repeating “hooks”. 4 ” Soott-Heron wrote in the introduction to his 1990 Now and Then collection of poems.Scott-Heron’s music and poetry showed his ddep interest in justice and civil rights, and he complained against the consumer society of the 1970s and 80s as well as the development of muclear technology.He was among the first artists to use h is music to attack the apartheid(種族隔離)in South Africa, long before the issue became the focus of a popular global campaign. 5 One of his most famous pieces was The Revolution Will Not Be Televised.In this piece, he criticized the role of race in the mass media and advertising age.
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A.But I don’t like football in Britain.
B.His work had a strong political element.
C.He grew up in Tennessee before moving to New York.
D.Scott was so crazy about politics that all of his songs are political.
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Every day we experiencc one of the wonders of the world around us without even realizing it It is not the amszing complexity of television. Nor the impressive tcchnology of transport The universal wonder we share and
Experience is our ability to make noises with our mouths, and so transmit ideas and thoughts to each other’s minds. This ability comes so naturally that tend to forget what a miracle(奇跡)it is.
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A.our ability to use language
B.the miracle of technology
C.the amazing power of nature
D.our ability to make noises with mouth
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A.Body language is unique to humans.
B.Animals express emotions just as humans do.
C.Humans have other powers of communication.
D.Humans are no different from animals to some degree.
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A.the development of body language
B.the special role humans play in nature
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