测序涉及确定的基础秩序 - 在基因或染色体 - DNA的是用字母A，丙，G和T代表的化学单位。

Sequencing involves determining the order of the bases — the chemical units of DNA that are represented by the letters A, C, G and T — in a gene or on a chromosome.

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有时候，可能是由基因造成。基因是单个细胞中的化学单位。它们传播指示，通知细胞应该做什么。一些时候，父母会把异常的基因传给自己的孩子。

Sometimes it may be caused by genes. genes are chemical units found in every cell. they carry the instruction telling cells what to do. sometimes, children receive abnormal genes from their parents.

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化学反应不能将元素分解成更小的单位。元素只含有一种原子。

An element cannot be broken down into simpler units by chemical reactions; it contains only one kind of atom.

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Most of chemistry has gone SI so every mass should be in kilograms.

大部分的化学遵守国际单位制,所以质量的单位应该是千克。

麻省理工公开课 - 固态化学导论课程节选

Chemically this is the smallest unit of charge.

化学上说，这是电荷的最小单位。

麻省理工公开课 - 固态化学导论课程节选