Autonomic Nervous system (exam 1) Flashcards
Which system, ANS or SNS, is voluntary or subonscious controlled
Somatic
Which system is involuntary or unconsciously controlled
ANS
Which system has a two neuron pathway
ANS
Which system has a single neuron pathway
SNS
Which system has a ganglia involved in the pathway
ANS
Which system does not have ganglia involved in the pathway
SNS
Sensory input from general and special senses, motor output to the skeletal muscle is what system
SNS
Sensory input from general and visceral senses motor output to cardiac, smooth muscle and glands
ANS
which system can excite or inhibit function using acetylcholine and norepinephrine
ANS
Which system only uses acetylcholine for excitation
SNS
Which system possess axons that are thin, some myelinated, other are not
ANS
Which system possesses axons that are thick and myelinated
SNS
What are autonomic plexuses
Collections of sympathetic postganglionic axons and parasympathetic preganglionic axons, as well as some visceral sensory axons
Where are sympathetic plexuses
from the spinal cord via the sympathetic trunk
Where are parsympathetic plexuses
From cranial and caudal repositories
Do sympathetic and parasympathetic plexuses interact
NO! they are close to one another, but do not interact or synapse with one another
What does the cardiac plexus do in the sympathetic nervous system
Increases heart rate and blood pressure
What does the Cardiac plexus do in the parasympathetic nervous system
Decreases heart rate
What does the pulmonary plexus do in the parasympathetic nervous system
Causes bronchoconstriction and increased secretion form mucous glands of the bronchial tree
What does the pulmonary plexus do in the sympathetic nervous system
Causes bronchodilation
What does the esophageal plexus do in the parasympathetic nervous system
controls the swallowing reflex
What three plexi make up the abdominal aortic plexus
Celiac plexus, superior plexus, and inferior mesenteric plexus (they are named for the artery they are around)
What is the function of theceliac plexus, superior mesenteric plexus, and inferior mesenteric plexus
Autonomic control of digestion
What is the function of the hypogastric plexus
Innervates pelvic viscera
Autonomic control of the urinary and reporductive functions
What are the two neurotransmitters that are used in the ANS
Acetylcholine (ACh) and Norepinephrine (NE)
who/what releases neurotransmitters in the ANS
Presynaptic cells
binding of neurotransmitters in the ANS has what kind of effect
either inhibitory or excitatory, depending on the specific receptor
where do neurotransmitters bind in the ANS
To specific receptors in the postsynaptic cell membrane
What does cholinergic mean
Uses acetylcholine as a neurotransmitter
What does it mean to be adrenergic
Pertains to cells using norepinephrine as their neurotransmitter
both the preganglionic and postganglionic axons in the parsympathetic division release what as their neurotransmitter
Acetylcholine and are thus cholinergic
Acetylcholine is released by what axons in the parsympathetic division
Preganglionic and postganglionic axons
What axons are cholinergic in the parasympathetic division
the preganglionic and postganglionic axons
The preganglionic axons in the sympathetic division release what neurotransmitter
Acetylcholine and are thus cholinergic
Most postganglionic axons of the sympathetic division release what neurotransmitter
norepinephrine (are thus adrenergic)
What axons are adrenergic
most of the psotganglionic axons of the sympathetic division
long preganglionic fibers are a characteristic of what division
Parsympathetic
short postganglionic fibers are a characteristic of what division of the ANS
Parasympathetic
Single preganglionic fibers are a characteristic of what division of the ANS
Parsympathetic
branched preganglionic fibers are a characteristic of what division of the ANS
Sympathetic
Short preganglionic fibers are a characteristic of what divsion of the ANS
Sympathetic
Long postganglionic fibers are a characteristic of what division of the ANS
The sympathetic divsion
Which division of the ANS is more specific
The parasympathetic divsion
which division of the ANS has a faster response to the ganglia
Sympathetic
Are Many visceral effector (organs) are innervated by postganglionic axons from both ANS divsions?
is it true that actions that act on organs from both divisions may oppose one another
YES
what is a way that the divisions can achieve opposing effects
one division can up-regulate or down-regulate the other
The ANS helps maintain homeostasis through what activity
Involuntary activity of autonomic reflexes or visceral reflexes
What are some ways that visceral (autonomic) reflexes maintain homeostasis
Smooth muscle contractions, cardiac muscle contractions, or secreation by glands that are mediated by autonic reflex arc in response to a specific stimulus
other examples: alteration of HR, changes in respiratory rate and depth, regulation of digestion, and alteration of pupil diameter
ex. Micturition reflex, which partly controls the release of urine
Micturition relfex is an example of what
autonomic or visceral relfex.
The ANS has reflexs that are comparable to spinal reflexes. What are they called
The autonomic (visceral) reflexes
Reduction of blood pressure is an example of what
an autonomic (visceral) reflex
is the autonomic sytem influenced by the cerebrum, hypothalamus, brainstem, and spinal cord
Some
sensory processing in the thalamus and emotional states controlled in the limbic system directly affect the hypothalamus
What is the hypothalamus
- integration and command center for autonomic functions
- contains nuclei that control visceral functions in both divisions of ANS
- Communicates with other CNS regions, including the cerebral cortex, thalamus, brainstem, cerebellum, and spinal cord
how does the cerebrum affect the ANS
conscious activities in the cerebrum affect hypothalamus control of the ANS
How does the brainstem affect the ANS
contains major ANS reflex centers
What affect does the spinal cord have on the ANS
Contains ANS reflex centers for defecation and urination
Which division of the ANS is more complex
The sympathetic division is more complex both anatomically and functionally
Where are the preganglionic neuron cell bodies of the sympathetic division housed
Lateral horns of T1-L2 regions
what is the path of the preganglionic sympathetic axons as they travel to the sympathetic trunk
travel with somatic motor neuron and exit the spinal cord via the anterior roots into the spinal nerve and then into the anterior rami, immediately after being in the anterior rami they turn and go into the white rami (white rami communicantes) and then into the sympathetic trunk
What are the sympathetic trunks
structures Bilateral the the medial column. house the paravertebral ganglia
The cervical portion of each sympathetic trunk is partitioned into how many ganglia
3
superior cervical ganglion, middle cervical ganglion, inferior cervical ganglion
what connects the spinal nerves to each sympathetic trunk
Rami communicantes
what are the white rami communicantes
They carry preganglionic sympathetic axons form the T1-L2 spinal nerves to the sympathetic trunk
The white rami communicantes are only associated with what spinal nerves
T1-L2
Preganglionic axons are myelinated or unmyelinated
Myelinated, gives white ramus the whitish appearance
Signal to the sympathetic trunk must always travel through what
White rami communicantes
What are gray rami communicantes
They carry the postganglionic sympathetic axons form the sympathetic trunk to the spinal nerve
Are gray rami communicantes myelinated or unmyelinated
Unmyelinated
Do the gray rami communicantes connect to all spinal nerves
Yes. including the cervical, sacral, and coccygeal
which rami is more laterally located
Splanchnic nerves are composed of what
Preganglionic sympathetic axons (thus myelinated)
Where are splanchnic nerves located
Run anteriorly form the sympathetic trunk to most of the viscera
Is the pelvic splachnic nerve part of the sympathetic nervous system
No! it is part of the parsympathetic nervous system
Give some examples of large splanchnic nerves in the sympathetic nervous system
Greater thoracic splanchnic nerves
Less thoracic splanchnic nerves
least thoracic splanchnic nerves
Lumbar splanchnic nerves
sacral splanchnic nerves
Where do splanchnic nerves in the sympathetic nervous system terminate
at the preverebral ganglia
Where are the prevertebral ganglia located
immediately anterior to the vertebral column on the anterolateral wall of the abdominal aorta
how are prevertebral ganglia named
For the arteries that they cluster around
examples: Celiac ganglia cluster around the celiac trunk
other examples superior mesentreric, and inferior mesenteric
What is different about prevertebral ganglia verse the sympathetic trunk (paravertebral ganglia)
prevertebral are single structures, rather than paired
are anteriro to the vertebral column on the anterior surface of the aorta instead of laterally located
they are located in the abdominopelivic region
What are the 3 prevertebral ganglia
Celiac, superior mesenteric, and inferior mesenteric ganglia
What are the four types of pathways sympathetic pathways
Spinal nerve pathway, postganglionic sympathetic nerve pathway, the splanchnic nerve pathway, The adrenal medulla pathway
What is special about the adrenal medulla pathway
What is unique about the spinal nerve proper
It is the only location where you have motor and sensory of the posterior and anterior in the same nerve
Explain the spinal nerve pathway
Sympathetic signal travels form the presnaptic cell body in the lateral horn out the anterior root into the spinal nerve proper onto the anterior spinal nerve into the white rami, then into the sympathetic trunk where it synapses and is sent out the gray rami onto the nerve which is on the same level as its starting spot
Explain the postganglionic sympathetic nerve pathway
Signal travels from the presynaptic cell body in the lateral horn through the anterior root through the spinal nerve proper, thought a white rami into a sympathetic trunk where it can now ascend or descend to another level then synapse onto a gray ramus and travel throught the spinal nerve
Explain the splanchnic nerve pathway
Presynaptic neurons leave the spinal cord via the anterior root, they travel into the spinal nerve proper into the anterior ramus, into the white ramus to the synamptic trunk where they jump onto a myelinated splanchnic nerve without synapsings. These nerves travel to the Prevertebral ganglia where they now synapse
What is another term for the parasympathetic division
Craniosacral division
what is the main concern of the parasympathetic division
conserving engery and replenishing nutrient stores
what cranial nerves are associated with the parasympathetic division
Oculomotor nerve (CNIII), facial nerve (CN VII), Glossopharyngeal nerve (CN IX)
and vagus nerve (CN X)
which three cranial nerves convey parasympathetic innnervention in the head
Oculomotor nerve (CN III)
Facial Nerve (CN VII)
Glossopharyngeal (CN IX)
What nerve is the source of parsympathetic stimulation for the thoracic and most abdominal organs
Vagus nerve (CN X)
What is the oculomotor nerve (CN III) associated ganglion (a) and parasympathetic activity
Ciliary ganglion
pupil constriction
ciliary mucles of the lens for accommodation (near vision/ reading)
Facial nerve (CN VII)
associated ganglion (a) and parasympathetic activity
Pterygopalatine ganglion
- lacrimal gland (tear production)
- nasal cavity ( mucous production)
- oral cavity ( saliva/mucous production)
- Submandibular ganglion
- Sumbmandibular and sublingual glands (saliva production)
Glossopharyngeal Nerve (CN IX)
Associated Ganglion (a) and parasympathetic activity
- otic ganglion
- parotid gland (saliva production)
Vagus nerve (CN X)
Associated Ganglion and Parasympathetic Activity
Postganlionic parasympathetics in the cranium always piggyback on what nerve
The trigeminal nerve
does the trigeminal nerve (CN V) have parasympathetic activity
No but it piggybacks the oculomotor (CN III), facial (VII), and glossopharyngeal nerves (IX)
The axons of the postsynaptic parasympathetic axons form the three cranial nerves Hitch-hike what nerve to get to their targets
The trigemial nerve (CN V)
Where is the caudal contribution of the parasympathetics located
sacral region of the spianl cord (S2-S4)
Preganglionic parasympathetic axons from the neuron cell bodies in the lateral horn contribute ot the formation of what?
the superior and inferior hypogastric plexus
Where do parasympathetic neurons from the superior and inferior hypogastric plexus synapse
close to or in the walls of the organs
What gets innervation from the superior and inferior hypogastric parasympathetic plexi
Distal portion of the large intestine
Rectum
Most reproductive organs
urinary bladder (contracts)
Distal ureters
Erection
When is the parasympathetic division most active
During times when the body must process nutrients and conserve energy
lack of extensive divergence in preganglionic axons is seen in what division of the ANS
Parasympathetic
Effects of which division of the ANS tend to be discrete and organized
Parasympathetics
Cardiac Plexus
Pulmonary Plexus
- Sympathetic innervation causes bronchodilation
- Parasympathetic pathway causes bronchoconstriction and increased secretion
Esophageal Plexus
Parasympathetic axons control the swallowing reflex
Abdominal aortic plexus
consists of celiac plexus, superior
Hypogastric plexus
- Innerates pelvic viscera=autonomic control of urinary and reproductive function
The superior cervical ganglion of the sympathetic nervous system sends sympathetic signals where
Eyes, blood vessels and sweat glands of head, and salivary glands, as well as to the cardiac and pulmonary plexuses
Larger splanchnic nerves of the sympathetic divison
- greater thoracic splanchnic nerves
- lesser thoracic splanchnic nerves
- least thoracic splanchnic nerves
- lumbar splanchnic nerves
- sacral splanchnic nerves
