Autonomic Nervous System Flashcards
what is the autonomic nervous system?
it regulates fundamental states and life processes
such as heart rate, BP, and body temperature
what is another name for the ANS?
visceral motor system
what are the primary organs of the ANS?
Viscera of thoracic and abdominal cavities, Cutaneous blood vessels, Sweat glands, Piloerector muscles
what is a visceral reflex?
unconscious, automatic,
stereotyped responses to stimulation involving
visceral receptors and effectors
what does the visceral reflex arc include?
Receptors: nerve endings that detect stretch, tissue damage,
blood chemicals, body temperature, and other internal stimuli
– Afferent neurons: lead to CNS
– Integrating center: interneurons in the CNS
– Efferent neurons: carry motor signals away from the CNS
– Effectors: carry out end response
what is an example of a visceral reflex?
baroreflex (helps to reduce blood pressure)
What are the 2 divisions of the ANS?
sympathetic & parasympathetic
what are the effectors for the pathways (autonomic vs. somatic)?
autonomic: glands, smooth muscle, cardiac muscle
somatic: skeletal muscle
what are the control for the pathways (autonomic vs. somatic)?
autonomic: involuntary
somatic: voluntary
what are the distal nerve endings for the pathways (autonomic vs. somatic)?
autonomic: varicosities
somatic: neuromuscular junctions
what are the efferent pathways for the pathways (autonomic vs. somatic)?
autonomic: 2 nerve fibers, synapse at ganglion
somatic: 1 nerve fiber, no ganglion
what are the neurotransmitters for the pathways (autonomic vs. somatic)?
autonomic: Ach & NE
somatic: Ach
what are the effect on target cells for the pathways (autonomic vs. somatic)?
autonomic: excitatory or inhibitory
somatic: excitatory
what are the effect on denervation for the pathways (autonomic vs. somatic)?
autonomic: hypersensitivity
somatic: flaccid paralysis
what is another name for the sympathetic division?
the thoracolumbar division
what is another name for the parasympathetic division?
the craniosacral division
where is the location of the ganglia for the sympathetic and parasympathetic?
symp: paravertebral ganglia adjacent spinal column and prevertebral ganglia anterior to it
para: terminal ganglia near or within target organs
what are the fiber lengths for the sympathetic and parasympathetic
symp: short preganglionic and long postganglionic
para: long preganglionic and short postganglionic
what is the neural divergence for the symp and para?
symp: extensive
para: minimal
what are the effects of system on symp and para?
symp: often widespread and general
para: more specific and local
what is the enteric nervous system?
the nervous system of the
digestive tract
what are axons that secrete Ach called?
cholinergic fibers
what is any receptor that binds Ach called?
cholinergic receptor
what are the two types of cholinergic receptor
muscarinic and nicotinic receptor
what are sympathetic postganglionic neurons that secrete NE called
adrenergic receptors
which adrenergic receptor is excitatory?
alpha-adrenergic
which adrenergic receptor is inhibitory?
beta-adrenergic
what is dual innervation?
nerve fibers from both parasympathetic and sympathetic
what is an antagonistic effect?
oppose each other
what is a cooperative effect?
the two divisions work together
what is an example of a cooperative effect?
salivary secretion
what is the parasympathetic effect on the eye?
pupil constricts
what is the sympathetic effect on the eye?
pupil dilates
what is vasomotor tone?
a baseline firing
frequency of sympathetics
what is vasoconstriction? (frequency-wise)
increase in firing
what is vasodilation? (frequency-wise)
decrease in firing
what does the sympathetic division prioritize in times of emergency
blood vessels to skeletal muscles
