Autonomic Nervous System Flashcards
(21 cards)
What are the two main divisions of the nervous system?
Central nervous system (CNS) and peripheral nervous system (PNS).
What are the two main divisions of the peripheral nervous system (PNS)?
Sensory (afferent) and motor (efferent).
What is the difference between the somatic and autonomic nervous systems?
Somatic controls voluntary muscles; autonomic controls involuntary organs.
What are the two divisions of the autonomic nervous system?
Sympathetic and parasympathetic nervous systems.
What is the function of the sympathetic nervous system?
Prepares the body for ‘fight or flight’ responses.
What is the main function of the parasympathetic nervous system?
Promotes ‘rest and digest’ functions.
Which cranial nerve is most important for parasympathetic output?
The vagus nerve (cranial nerve X).
What neurotransmitter is used by preganglionic parasympathetic neurons?
Acetylcholine (ACh).
What neurotransmitter is used by postganglionic parasympathetic neurons?
Acetylcholine (ACh).
What type of receptor does acetylcholine bind to in ganglia?
Nicotinic cholinergic receptors.
What type of receptor does acetylcholine bind to at target organs?
Muscarinic cholinergic receptors.
What neurotransmitter is primarily released by postganglionic sympathetic neurons?
Norepinephrine (noradrenaline).
What receptors are activated by norepinephrine in the sympathetic system?
Adrenergic receptors (alpha and beta types).
Where are sympathetic ganglia located relative to the spinal cord?
Near the spinal cord (sympathetic chain).
Where are parasympathetic ganglia typically located?
Near or within the target organ.
How does sympathetic stimulation affect heart rate and pupils?
Increases heart rate and dilates pupils.
What is dual innervation?
When an organ receives both sympathetic and parasympathetic input.
What is an autonomic ganglion?
A cluster of neuron cell bodies where pre- and post-ganglionic neurons synapse.
What effect does parasympathetic stimulation have on the digestive system?
Stimulates digestion and secretion.
What effect does sympathetic stimulation have on the digestive system?
Inhibits digestion and decreases motility.
What does the enteric nervous system regulate?
Function of the gastrointestinal tract including motility and secretion.
