This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated. NEW SHARON, Iowa -- Three young brothers are dead after a crash in Mahaska County Thursday. The Iowa State Patrol says a truck driven by 41-year-old Shawn Schippers collided with a car driven by 16-year-old Jamie Singletary at the intersection of Queens Avenue and 130th Street, east of New Sharon, around 1:00 p.m. They say both vehicles went into the ditch.
Video: Sympathetic Nervous System: Definition, Function & Effects. The autonomic nervous system is the portion that controls all of the involuntary functions of the body. This includes the body's response to emergency situations. In this article, we discuss the sympathetic nervous system and its responses under these circumstances.
Quick Answer. Involuntary activities are controlled by the autonomous nervous system, whose main component is a part of the brain stem called the medulla oblongata. This system, as a subset of the peripheral nervous system, functions outside the brain and spinal cord and is composed of the sympathetic and parasympathetic nervous systems. The medulla oblongata directly controls heartbeat, blood pressure, breathing and digestion. The sympathetic nervous system controls the body's fight-or-flight response, which quickly increases blood flow and breathing rate in response to danger or excitement. The parasympathetic nervous system does the opposite; it reverses the changes done by the sympathetic nervous system in order to calm the body, although its response is slower and occurs over the course of a few minutes.