Piss and shitting

Description:You do not control your internal sphincter for urination. Same goes for your bladder. You cannot control when the muscular walls of it begin to contract. You can, however, control your external urethral sphincter, which is why when you have to pee really bad, it gets "hard" to hold it in. You're basically using your control of the one voluntary peeing muscle to fight against both the badder contracting and the internal sphincter opening. Most organs have both parasympathetic and sympathetic innervation, which operate reciprocally and synergistically to produce coordinates responses, meaning that they balance each other out in most cases.

Views: 4189 Date: 2018-11-13 Favorited: 45