来自《耶鲁大学开放课程：生物医学工程探索 第3集 第3集》

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  The corresponding half of the
  与任何单链配对的
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  ladder that corresponds to any given ladder,
  另一条单链
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  let's say the black DNA molecule
  比方说与蓝色DNA分子
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  that corresponds to the blue one
  配对的黑色DNA分子
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  is not just a mirror image.
  并不是蓝色DNA分子的镜像
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  We call it the complement and each strand of DNA,
  我们称之为互补链
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  each polymer of DNA
  每个DNA聚合物
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  that you could make or you could draw has only one complement
  都只有一种互补链
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  and that complement has the following features.
  互补链有以下特点
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  One, its chain is oriented in the
  一 这些DNA单链
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  opposite direction: where this one goes 5' to 3',
  方向相反 一条从5'端到 3'端
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  this one goes 3' to 5'.
  另一条从3'端到5'端