Remember that this molecule, let's look at the blue one wouldn't be the same if I turned it upside down.

让我们记住,如果我把蓝色的,单链倒过来,那么这条链和原来不一样了

耶鲁公开课 - 生物医学工程探索课程节选

It wouldn't be the same if I turned it upside down because the carbons - the rings here, the pentose's would all be turned over, the chemistry would look different and the sequence of bases would look different.

记住单链倒过来,就和原来不一样了,这是因为碳原子和糖环结构,戊糖会翻转,使得这个化学结构看起来不一样了,碱基的顺序也不一样了

耶鲁公开课 - 生物医学工程探索课程节选