Course Hero Logo

ANS typed - Autonomic Nervous System Slide 3 Autonomic...

Course Hero uses AI to attempt to automatically extract content from documents to surface to you and others so you can study better, e.g., in search results, to enrich docs, and more. This preview shows page 1 - 3 out of 7 pages.

Autonomic Nervous SystemSlide 3 Autonomic Nervous SystemViscera are your internal organs- so this is the nervous system that mediates functionality in mostinternal organsLike pupil diameter, heart rate, blood pressure, digestion, secretion of hormonesFunction is to provide homeostasisANS reflex example - Baroreceptors send information back and determine outflow of theautonomic nervous system to control blood pressure throughout the bodyThe ANS is not like a normal light switch that turns on and off. The ANS is always active. It actsmore like a dimmer switch.This continuous outflow from the ANS is called tonic activity. The neurons are always firing. Youcan up or down regulate by increasing or decreasing inputs from the ANSTwo divisions are the sympathetic and parasympathetic nervous system.Most organs tend to be innervated by both systemsSympathetic usually stimulates activity and parasympathetic inhibits the activity.The divisions use different chemical signals, different neurotransmitters, different distribution ofnerves that release the ANS neurotransmitters and a different distribution of receptors to receivethe signalSlide 4 ANS homeostasisThese are things the ANS controls at individual organsThe ANS does not require a signal from the CNS however its activity can be modified and up ordown regulated by signals from the higher CNSSignals originate in the hypothalamus, pons, medulla, spinal cord and are affected by higher CNSinputs (like for emotional responses- when youre embarrassed with toilet paper on your shoe.Allows for flushing on your face and the butterfly feeling and if you start sweating. )Slide 5 ANS + MNSPart of the PNS (sensory system) which is the afferent systemThe ANS and the MNS (motor) both make of the efferent (outflow) pathways to the peripheryMNS is controlled by the CNS and ANS is modulated by the CNSMNS outflow is always excitatory. It excites the effector tissue (muscle). ANS is tonic so it canincrease or decrease activityANS uses Ach and NE ( the sole neurotransmitters in AN neurons)The MNS uses only Ach (cholinergic)Norepinephrine is always called noradrenalineIn addition to being released at axons, the ANS neurotransmitters can also be released atvaricosities which are swellings along the axons prior to the axon terminalThere are some non-adrenergic and non-cholinergic neurons which can release instead substanceP or NO or ATP. It’s based on whether its sympathetic or para based on its origin not on whichneurotransmitter it secretes.
Slide 6 ANS is efferent peripheryThis is an efferent system and it sends signals to the peripheryPathway is composed of two neuronsFirst neuron is preganglionic neuron. The cell body is in the spinal cord or in the brain stem.

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 7 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Spring
Professor
N/A
Tags

Newly uploaded documents

Show More

Newly uploaded documents

Show More

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture