The autonomic nervous system Stellek Bálint Sándor 2016.10.27. The autonomic nervous system (ANS) is a division of the peripheral nervous system (other division is somatic nervous system) It influences the function of internal organs It acts largely unconsciously It regulates bodily functions such as heart rate, digestion, urination, respiratory rate etc. Within the brain, the ANS regulated by the hypothalamus The peripheral nervous system (PNS) is the part of the nervous system that consists of the nerves and ganglia outside of the brain and spinal cord. The main function of the PNS is to connect the central nervous system (CNS) to the limbs and organs, essentially serving as a communication relay going back and forth between the brain and spinal cord with the rest of the body. Unlike the CNS, the PNS is not protected by the bone of spine and skull, or by the blood–brain barrier, which leaves it exposed to toxins and mechanical injuries. https://www.freelapusa.com/wp-content/uploads/2013/10/Sympathetic-System.gif

The autonomic nervous system is divided into two part: Sympathetic nervous system Emerges from the spinal cord in the thoracic and lumbar areas ("thoracolumbar outflow”) Parasympathetic nervous system It has “craniosacral outflow”, meaning that the neurons begin at the cranial nerves and sacral spinal cord. http://georgi-georgiev.com/demo/websites/nervous-system/img/spine-animation.gif

Sympathetic nervous system It’s primary process is to stimulate the body's fight-or-flight response And it constantly active at a basic level to maintain homeostasis. http://www.daviddarling.info/encyclopedia/S/spinal_cord.html https://s-media-cache-ak0.pinimg.com/originals/cb/d9/a8/cbd9a8579334b1e0a257c0fec5585427.gif

Parasympathetic nervous system The parasympathetic nervous system (PSNS) is the other divisions of the autonomic nervous system The parasympathetic system is responsible for stimulation of "rest-and-digest" or "feed and breed” activities. These occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion and defecation. It has 3 main division (nerves): Cranial nerves, vagus nerve and pelvic splanchnic nerves http://www.s-cool.co.uk/gifs/g-pe-contro-dia03b.gif

Two kinds of neurons involved in the transmission of any signal through the sympathetic and parasympathetic system: pre-ganglionic and post-ganglionic Ganglion is a nerve cell cluster or a group of nerve cell bodies located in the autonomic nervous system. Ganglia house the cell bodies of afferent nerves. http://droualb.faculty.mjc.edu/Course%20Materials/Physiology%20101/Chapter%20Notes/Fall%202007/figure_11_03_labeled.jpg In the sympathetic and parasympathetic nervous system, efferent nerve signals are carried from the central nervous system to their targets by a system of two neurons. The axons of preganglionic parasympathetic neurons are usually long, extending from the CNS into a ganglion that is either very close to or embedded in their target organ (sympathetic is the opposite).