Lecture 15 - (ANS) Neuroanatomy And Divisions Flashcards
What functions does the Autonomic Nervous system do?
All involuntary/vegetative functions
Is the Autonomic Nervous System Afferent or efferent?
Entirely efferent but is regulated by afferent inputs
How does the ANS differ to the Somatic/voluntary system?
Somatic is responsible for voluntary actions like skeletal muscle contractions
ANS is completely separate, does involuntary actions
What are the 2 divisions of the (efferent) ANS?
Sympathetic
Parasympathetic
What does the sympathetic nervous system do?
Resonds to stressful situations
Fight or flight responses
What are some examples of responses the sympathetic nervous system may produce?
INC HR (+ve chronotropy)
INC Force of contraction (+inotropy)
INC BP
What is the parasympathetic nervous system responsible for?
Regulates basal activities
Rest and digest responses
Which part of the spinal column do the Preganglionic neurones of the SYMPATHETIC nervous system emerge from?
Thoracic
Lumbar
What key endocrine gland receives sympathetic stimulation from the AUTONOMIC nervous system?
Adrenal gland
(Adrenal medulla)
Where do the Preganglionic neurones of the Parasympathetic nervous system originate from?
Craniomedullary region
Sacral region
What is the main Cranial nerve which provides lots of Parasympathetic innervation?
Vagus Nerve/Cranial nerve X
Are the Preganglionic neurones of the ANS myelinated or unmyelinated?
Myelinated
Are the Postganglionic neurones of the ANS myelinated or unmyelinated?
Unmyelinated
What is the relative lengths of the Preganglionic and then postganglionic neurones in the parasympathetic nervous system?
Preganglionic neurones = Long
Postganglionic neurones = Short
What is the relative lengths of the Preganglionic and then postganglionic neurones in the sympathetic nervous system?
Preganglionic neurones = Short
Postganglionic neurones = Long
What neurotransmitter is used by all pre-ganglionic neurones?
ACh
They are cholinergic
What type of receptors are present at the synaptic junction between the pre and postganglionic neurone in the ANS (both the sympathetic and parasympathetic)?
Nicotinic Acetylcholine receptors (nAChr)
What type of receptor is the nAChr that is present between the pre and postganglionic neurones in both the sympathetic and parasympathetic NS?
Ligand gated ion channel
What type of receptor is present on the effector tissues following a postganglionic neurone in the PARASYMPATHETIC nervous system?
Cholinergic:
Muscarinic (ACh) receptors