Autonomic Nervous System Flashcards
What do both the ANS and SNS respond to stimulus from?
The sensory nervous system
What type of system is the SNS and ANS
Motor Systems
How many axons does the SNS use to travel from the spinal cord to a skeletal muscle fiber
1
How many axons does the ANS use to travel from the spinal cord to smooth muscle, cardiac, or a gland?
2
How do axons in the ANS communicate with each other?
Via ganglia (one labeled pre-ganglionic, the other post-ganglionic)
The axons in the SNS are only…
excitatory
The axons in the ANS are
both excitatory and inhibitory
Where is the soma of preganglionic neurons found? (ANS)
brain/spinal cord
Where is the autonomic ganglia found?
PNS
What does the parasympathetic division of the ANS do?
Conserves energy and replenishes nutrient storage (homeostasis)
What does the sympathetic division do?
Increases alertness and metabolic activity (fight or flight)
Parasympathetic Division
Preganglionic axon is very long coming from the soma to the ganglion and is myelinated
The ganglia are close to the terminal ganglion (target) or found in the walls of the target (intermural ganglion)
Second axon is nonmyelinated
What is the parasympathetic division also known as?
The craniosacral division
Where are the somas of the parasympathetic nervous system?
Sacrum and cranium
Which cranial nerves have autonomic fibers running with them?
Oculomotor (CN III) (extintric muscles of eye)
Facial (CN VII) (lacrimal gland/submandibular/sublingual gland)
Glossopharyngeal (CN IX)
Vagus (CN X)(interal organs in anterior cavity)
Sympathetic Division
Short, myelinated preganglionic axon. Synapse in the sympathetic trunk ganglia (lateral to the spinal cord). Referred to as white rami
Postganglionic axon is referred to as grey rami (can both be referred to as grey/white rami communicates)
What is the sympathetic nervous system also known as?
Thoracolumbar division
(one stimulus can activate all neurons up and down the trunk)
What system activates the adrenal medulla?
Sympathetic Nervous System. Releases epinephrine and norepinephrine.
What neurotransmitter does the sympathetic and parasympathetic release?
Aceteylcholine (excitatory effect)
What receptors do preganglionic neurons have?
Nicotinic
What receptors do parasympathetic target cells have?
Muscarinic
What receptors do sympathetic axons which stimulate blood vessels and sweat glands have?
Acetylcholine to muscarinic.