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SSS 2008-05-20

时间:2010-05-14 01:20来源:互联网 提供网友:0922013129   字体: [ ]
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This is scientific American's 60-Second Science, I'm Karen Hopkin, this'll just take a minute.

 

If there’s anything better than a fresh, ripe, tomato, it’s a gigantic fresh, ripe tomato. And thanks to a couple of mutations, that’s exactly what we all enjoy every time we grab a tomato from the farmer’s market or the grocery store. In the wild, tomato plants actually produce some pretty small fruit. Today’s cultivated varieties serve up tomatoes that are a thousand times larger. This yummy enormity comes from mutations that affect the activity of two genes3: one that controls cell division, so the more cells there are in a tomato, the bigger that tomato will be; and another that controls how many seed-bearing compartments4 each fruit has. Again, the more compartments the bigger the fruit.

The compartment-number mutation1, discovered by scientists at Cornell University, is described online in the current issue of Nature Genetics. The researchers found that no strains of wild tomato carry this mutation, which affects a gene2 called fasciated. While all of the large-fruited modern varieties they surveyed have it, this suggests that the mutation occurred relatively5 recently in tomato history, and that breeders then shared it with all their tomato-loving friends. So you can thank those fasciated mutants for teeing up your next BLT.

 

Thanks for the minute, for Scientific American 60-Second Science, I'm Karen Hopkin.

 


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1 mutation t1PyM     
n.变化,变异,转变
参考例句:
  • People who have this mutation need less sleep than others.有这种突变的人需要的睡眠比其他人少。
  • So far the discussion has centered entirely around mutation in the strict sense.到目前为止,严格来讲,讨论完全集中于围绕突变问题上。
2 gene WgKxx     
n.遗传因子,基因
参考例句:
  • A single gene may have many effects.单一基因可能具有很多种效应。
  • The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
3 genes 01914f8eac35d7e14afa065217edd8c0     
n.基因( gene的名词复数 )
参考例句:
  • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
  • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
4 compartments 4e9d78104c402c263f5154f3360372c7     
n.间隔( compartment的名词复数 );(列车车厢的)隔间;(家具或设备等的)分隔间;隔层
参考例句:
  • Your pencil box has several compartments. 你的铅笔盒有好几个格。 来自《简明英汉词典》
  • The first-class compartments are in front. 头等车室在前头。 来自《简明英汉词典》
5 relatively bkqzS3     
adv.比较...地,相对地
参考例句:
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
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TAG标签:   SSS  mutation
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