ANS Flashcards
When sympathetic and parasympathetic divisions are working together but serving opposite effects.
Serve same visceral organs, cause essentially opposite effects.
Dual Innervation
What ANS division is “resting and digesting”
Parasympathetic Division
In the parasympathetic division describe the length of the pre and post ganglionic fibers
Preganglionic- short fibers
Postganglionic - long fibers
Describe the origin of the pre and post ganglionic fibers for the parasympathetic division
preganglionic- craniosacral origin
post ganglionic - close to the spinal cord (called intramural ganglia)
what division is called “fight or flight”
Sympathetic division
Describe the lengths of the pre and post ganglionic fibers in the sympathetic division
preganglionic- shot
postganglionic - long
describe the origin of the pre and postganglionic fibers in the sympathetic nervous system
preganglionic- thoracolumbar origin
postganglionic - ganglia are close to the spinal cord
Which branch is voluntary of the efferent division?
sends signals from the CNS to skeletal muscles
Somatic Nervous System
What branch is involuntary in the efferent division?
Transmits signals from the CNS to skeletal muscle, smooth muscle, and glands
Autonomic Nervous System
(“Automatic”)
The function of the ANS is to maintain what?
Homeostasis
keeps conditions inside the body within optimal ranges
- digestion of food and maintaining blood pressure
What neurotransmitter does the somatic nervous system (SNS) release
Acetylocholine (ACh) from the synaptic knob to excite muscle fiber
Is the somatic nervous system controlled consciously or unconsciously?
Consciously
What is the effector organ for the somatic nervous system?
skeletal muscle
what is the response (excitatory or inhibitory) for the somatic nervous system
Excitatory
How many neurons are present in the Somatic nervous system?
One
Is the autonomic nervous system controlled unconsciously or consciously?
unconsciously
what is the effector organs for the autonomic nervous system
cardiac and smooth muscle as well as glands
Is the autonomic nervous system excitable or inhibitory
Both
What is the neurotransmitter released for the preganglionic cell in the autonomic nervous system
ACh
What is the neurotransmitter released for the postganglionic cell in the autonomic nervous system
ACh or NE
How many neurons are in the autonomic nervous system?
2
what part of the brain:
Integration and command center for autonomic functions; involved in emotions (fight or flight)
Hypothalamus
What part of the brain:
Contains major ANS reflex centers
Brainstem
what part of the brain:
Contains ANS reflex centers for deification and urination
Spinal cord
Is the ANS preganglionic cell myelinated or unmyelinated?
thin and unmyelinated
Does the somatic nervous system have a myelinated or unmyelinated axon?
Myelinated (Fast propagation)
Is the ANS postganglionic cell myelinated or unmyelinated?
very thin and unmyelinated
much slower in comparsion to SNS
What is the term when you have multiple preganglionic neurons and they synapse on one post ganglionic neuron?
lots of control, one target response
Convergence
what is the term when you have branches of axons from one preganglionic neuron that synapses w numerous post ganglionic neurons
increases the effect by targeting many areas
Divergence
what type of fiber is it when sympathetic postganglionic axons release
norepinephrine (NE
Adrenergic fibers
what type of fiber is it when parasympathetic system postganglionic axons
release Ach
cholinergic fibers
effector cells of postganglionic parasympathetic
fibers
* Different types: M1, M2…
* Activated by muscarine
* Atropine is antagonist
muscarinic receptors
all postganlionic neuron receptive regions; hormone
producing cells of adrenal medulla
* Activated by nicotine
Nicotinic receptors
type of receptor:
bind NE; found in effector cells of
postganglionic sympathetic fibers
– All G-protein mediated
adrenergic receptors
