It is no longer tethered to the nucleus so there is no energy stored in the system.

它已经不再受原子核的吸引,所以这个系统中没有能量储存了。

麻省理工公开课 - 固态化学导论课程节选

In some cells they're recycled, that is the cell is able to take up the neurotransmitter after it's released and restore it, but most often there are enzyme systems inside the pre-synaptic membrane where those neurotransmitters are synthesized.

在一些细胞中神经递质可以循环利用,这些细胞可以吸收,已经释放出的神经递质并重新储存起来,但更常见的是突触前膜中含有酶系统,在此合成神经递质

耶鲁公开课 - 生物医学工程探索课程节选

The ones who would seek out calories, the ones who could store and not waste energy, those with an efficient metabolism-- that is those people who took in calories and banked them into their body fat and stored against subsequent famine-- are the ones who would do the best under these circumstances.

那些寻找能量的人,那些储存而不浪费能量的人,那些有着高效代谢系统的人,那些人可以将摄入的热量储存为机体脂肪,以用于对抗即将到来的饥荒,在早先的情况下他们是最适应环境的

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选