You know that messenger RNA is read in three base units called codons, and so this particular piece of messenger RNA is drawn in this cartoon in three base pair units.

RNA是按每三个碱基组成一个密码子,进行翻译的,在这幅动画中所画的mRNA,就是按三个碱基一组的方式来描绘的

耶鲁公开课 - 生物医学工程探索课程节选