There are 64 combinations of three bases and I only need to describe 20, so there's combinations to spare.

三个一组的碱基产生六十四种组合,而我只需对应二十种氨基酸,所以一种氨基酸会对应不同密码子

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How many combinations of codons are there if there's three bases and four possibilities at each base?

那密码子的组合方式到底有几种呢,三个位点,每个位点四种选择

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Why are there three bases in a codon?

为什么一个密码子有三个碱基呢

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