Autonomic nervous system Flashcards
What do autonomic motor fibres innervate?
Smooth muscle + glands (e.g salivary gland)
Gastro-intestinal system for the most part (has its own nerve supply; activity only regulated by autonomic nervous system)
Describe the structure of autonomic motor pathways
2 neurones in series; cell body in CNS with axon extending to autonomic ganglion where it synapses; axon from cell body travels to the effector organ
What are the subdivisions of the autonomic nervous system?
Sympathic and parasympathetic
Many organs will receive innervation from both (antagonistic)
From where does the sympathetic nervous system arise in the spinal column?
T1-L2
What is the function of the sympathetic nervous system?
Moderates visceral function
increases HR, peristalsis, sweating (fight or flight)
What is the function of the parasympathetic nervous system?
Rest and digest
What is different about the nervous supply of the adrenal medulla?
There is no post-ganglionic fibres
What’s different about the sympathetic nervous control for organs in the abdominopelvic cavity?
Ganglia not in sympathetic chain; uses plexuses and sphlachnic nerves; synapses in collateral ganglia.
What is Hilton’s law?
Connection between dermotomes and myotomes
Whats different about sympathetic control of the adrenal medulla
There is no pre/post ganglionic neurons just one cell from the spinal cord straight out.
How do spinal nerves leave the vertebrae?
Through the anterior root of the spinal cord
From where does the parasympathetic system arise?
Cranial nerves III, VII, IX, X and sacral nerves S2-S4
