来自《耶鲁大学开放课程：生物医学工程探索 第6集 第6集》

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  and those changes lead to differences in
  而这些变化导致
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  which fraction of the total genes in the chromosomes
  在特定细胞中 染色体组的全部基因中
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  are being expressed by a particular cell.
  只有一部分表达出来
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  This is what makes cells different,
  这就是细胞产生差异的原因
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  the number and quantity of the genes that they express.
  即表达的基因在数量和质量上的差异
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  Out of all the genes that are on the human genome
  人类基因组全部基因中的
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  which fraction is this particular cell using,
  特定细胞所表达的基因片段
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  which fraction is it expressing
  细胞表达的是哪段基因
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  determines what proteins are present in the cell,
  决定了细胞中存在什么样的蛋白
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  determines what work
  决定了细胞会有什么样的功能
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  or what activities the cell can engage in.
  或者参与何种生命活动
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  What's changing along here is the
  因此这里改变的是