Electrical signals can't do that, but the nervous and endocrine systems aren't totally separated.

电信号不能做到这一点，但神经和内分泌系统并没有完全分离。

But chemicals that target the endocrine system have been known to break that rule.

但众所周知，针对内分泌系统的化学物质会打破这一规则。

The endocrine system. The two systems that control body activities are the endocrine system and the nervous system.

前者通过一种叫做激素的化学信使来发挥控制作用。激素由多种内分泌腺体产生，它们将激素直接释放进入血中。