J. Craig Venter and his colleagues recently announced that they had created

游客2023-08-20  19

问题     J. Craig Venter and his colleagues recently announced that they had created the first cell to run on a fully artificial genome(基因组). So what’s next for this man-made strain of microscopic(精微的)Mycoplasma mycoides(丝状支原体)and the new technology?
    The "synthetic cell" achievement has been praised, condemned and undercut, but it has yet to fully demystify life’s underlying code, the genome.
    Researchers built much of the bacterium’s(细菌)genome without fully understanding the function of many of the million-plus base pairs involved. About half of the genes, in fact, are still " a complete black box," said Richard Roberts of New England Biolabs, Inc. , in a commentary after Venter’s talk.
    But a bit like complex builder sets can help illuminate some of the basic rules of physics and engineering, scientists are hoping that constructing—and deconstructing and reconstructing—whole genomes will help them better understand genomic principles. Scientists, for instance,, don’t yet know what role or importance the order of genes in the genome plays. They have seen that in some cases, genes can have their order exchanged with little visible outcome on life, whereas, specific sequence might be more important elsewhere on the genome.
    Although the researchers based their synthetic genome on the natural one, their cell did not behave exactly the same, Venter noted. Usually when you mess around with the inner workings of a cell, especially its genetic code, growth rate tends to slow. With this one, however, there was a huge increase in the growth rate.
    So how long will it be until scientists can synthesize genomes for other, more complex forms of life?
    " One of the group’s long-term goals," said Venter, " is to develop a universal recipient cell, into which researchers can plug a variety of synthetic genomes and see how they run. " " And in the future" , he proposed, " it might be cheaper for scientists to synthesize simple organisms than to grow them. "
    Roberts is happy to see the synthetic genome advance as a way to refocus research interest and attention on bacteria, which he calls " cute ... lovely little organisms. " In particular, being able to better understand the genomes of bacteria can have broad health implications for people, who host some 100 trillion microbial cells in and on their bodies.
    The field of genomics, however, can be slow-going and riddled with many costly mistakes. Just one error small in earlier attempts to assemble a synthetic code set the researchers on Venter’s team back months. But James Watson, former head of Cold Spring Harbor Laboratory whose co-discovery of DNA more than 50 years ago helped to lay the foundation for this work, was pleased by the speed of progress. "We’ve been so much more successful that you might have predicted," he said at the symposium. [br] We can learn from the first paragraph that______.

选项 A、a fully artificial genome was built
B、a synthetic cell began to ran
C、a genome was built to create a cell
D、the first synthetic cell was created

答案 D

解析 由题干提示定位到第一段。D)“第一个人造细胞产生了”跟第一段第一句中“已经在一个完全人工的基因组上创造出了首个细胞”语意一致,因此为正确答案。
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