Chap 18 Flashcards
Two branches of autonomic ns
Sympathetic and parasympathetic
Sympathetic
Fight or flight
Parasympathetic
Rest and digest
Somatic sensory
Nerve impulses from special senses
-consciously perceived
Visceral sensory
Sensory input that is not consciously perceived from receptors
-blood vessels
Somatic motor
Consciously controlled muscle movement
-skeletal muscles
Autonomic motor
Motor output not consciously controlled
-smooth muscle and cardiac muscle
Autonomic sensory neurons (location and where do they go)
Located in
-visceral organs
-blood vessels
Sent to the CNS
Integrating centres
Located in central nervous system
Autonomic motor neurons
From CNS to various effector tissues to regulate activity of
-smooth muscle
-cardiac muscle
-glands
Enteric division ENS
Specialized network of nerves and ganglia
-independent network within wall of GI tract
-brain of the gut
Somatic nervous system process
-From spinal cord
-to myelinated motor neuron
-directly to effector
Autonomic nervous system process
-from spinal cord
-more specifically preganglionic neuron
-to preganglionic axon
-to autonomic ganglion
-postganglionic axon
-to effector organ
Anatomical differences in ANS divisions
-length of preganglionic and postganglionic axons
-number of preganglionic axon branches
-location of ganglia
Sympathetic division has the ______ located in the _____
-preganglionic neurons
-T1 to L2
Parasympathetic preganglionic neurons located in _______ and _______
-brain stem nuclei
-S2 to S4
What division is found in the thoracolumabr division
Sympathetic division
Sympathetic Preganglionic neurons location
Located in the
-12 thoracic segments
-first two lumbar segments
T1-S2
Mass activation
SNS works to prepare for fight or flight
-everything kicks into gear
PNS division appearance of pre and postganglionic axon
Pre- long axon unbranched
Post- short axon
SNS pre and postganglionic appearance
Pre- short and branching
Post- long
Sympathetic ganglia
Sites of synapses between sympathetic preganglionic and postganglionic neurons
Three types of sympathetic ganglia
-sympathetic trunk ganglia
-prevertebral ganglia
-postganglionic axons
Sympathetic trunk ganglia
Vertical row on either side of vertebral column
Prevertebral ganglia
Lies anterior to vertebral column and close to the large abdominal artieries
Postganglionic axons
From prevertebral ganglia innervate organs below diaphragm
Preganglionic neurons of the SNS location
Located: T1-L2
-lateral horns of gray matter
Three general groups of autonomic ganglia
-Sympathetic trunk ganglia
-prevertebral ganglia
-postganglionic axons
Sympathetic ganglia
Sites of synapses between sympathetic preganglionic and postganglionic neurons
Sympathetic trunk ganglia
Vertical row on either side of vertebral column
Prevertebral ganglia
Lies anterior to the vertebral column, close to large abdominal arteries
Goes to various organs
Postganglionic axons
From pre-vertebral ganglia
-Innervates organs below the diaphragm
Sympathetic trunks location
anterior to spinal nerves and lateral to vertebral column
Sympathetic trunk ganglia function
House sympathetic ganglion is neuron cell bodies
-one ganglion associated with each spinal nerve
Types of prevertebral ganglia
-celiac
-superior mesenteric
-cervical ganglia inferior mesenteric
-sympathetic splanchnic nerves
Celiac ganglia
Location: adjacent to origin of celiac artery
-preganglionic: T5-T9
-postganglionic: Innervates stomach, spleen, liver, gallbladder, proximal duodenum, pancreas
Superior mesenteric ganglia
Integrating centres located
In the central nervous system
Is the somatic motor neuron myelinated or non myelinated?
Myelinated
A myelinated nervous system is
Sympathetic nervous system
Is the ANS myelinated or not myelinated
Preganglionic axon: is myelinated
Postganglionic: not myelinated
In the ANS pathway what type is the first neuron
Preganglionic neuron
Preganglionic neuron of the ANS
Cell body is in the brain or spinal cord
-first neuron in the ANS
What excites the second neuron in the ANS
Acetylcholine
Ganglionic neuron in the ANS
-thin unmyelinated
Also called postganglionic as it comes after
-extends to effector cells
Post ganglionic neurons function
Extend to effector cells
Celiac ganglia postganglionic axons innervate what
Innervates stomach, spleen, liver, gallbladder, proximal duodenum, pancreas
Postganglionic axons of superior mesenteric ganglia Innervates what
-distal duodenum
-pancreas
-small intestine
-proximal large intestine
-proximal ureteres
Cervical ganglia
Found in the cervical areas of the spinal cord
-superior cervical ganglion
-middle and inferior cervical ganglia
Superior cervical ganglion postganglionic axons innervate what
Head and neck
Middle nad inferior cervical ganglia postganglionic Innervates
Thoracic viscera
Inferior mesenteric ganglia post ganglionic axons innervate
-hypogastric structure
-distal colon
-rectum
-reproductive organs
-bladder and ureter
White ramus
Connects the spinal nerve to presympathetic
-myelination
Grey ramus
Connects postganglionic to spinal nerve
-unmyelinated
Origin of PNS preganglionic neurons
S2-S4
Parasympathetic division vs sympathetic division: preganglionic neurons
P: long preganglionic axon
S: short, branching preganglionic axon
Parasympathetic division vs sympathetic division: postganglionic
P: short postganglionic axon
S: long postganglionic axon
Location of Parasympathic location (structure)
Brain stem, last portion of the spinal cord (sacral)
Terminal ganglia (four)
-ciliary
-pterygopalatine
-submandibular
-optic
Ciliary ganglia
Preganglionic: oculomotor nerve
Postganglionic: ciliary and iris muscles, help with vision
Pterygopalatine ganglia
Preganglionic: passes through facial nerve
Postganglionic: lacrimal glands, nose gland, mouth and palate
Submandibular ganglia
Preganglionic: passes with facial nerve
Postganglionic: submandibular and sublingual salivary glands
Otis ganglia
Preganglionic: pass with glassopharyngeal nerve
Postganglionic: parotid gland (salivary gland)
Vagus nerve
Innervates the heart, lungs, lower abdominal organs
Activity of vagus nerve in thoracic organs
Increases mucous production, decreases airway diameter and decreases heart rate/contraction
Activity of vagus nerve in abdominal organs
Increases smooth muscles motility and secretory activity in GI tract
Preganglionic axon sympathetic NS releases
Releases neurotransmitter called Ach
Postganglionic neuron in sympathetic ns releases
Adrenergi (NE)
Common neurotransmitter released by pre and post ganglionic axon in the sympathetic ns
Pre: ACh
Post: NE
Parasympathetic and sympathetic ns secretions
Sympathetic effects
Adrenergic
-gears body for action
-MASS ACTIVATION
-fight or flight
Parasympathetic effects
Cholinergic effects
-conserves body’s energy
-rest and digest
Autonomic plexuses
Located: thorax, abdomen, pelvis
-creates reflexes that: blood pressure and heart rate, digestion, opening and closing of sphincters (defecation and urination)
Cardiac plexus
Increased heart rate and blood pressure (inc SNS)
Decreases heart rate (PNS)
Pulmonary plexus
SNS- bronchodilation
PNS- bronchoconstriction and inc secretion from bronchial tree
Esophageal plexus
PNS-swallowing reflex
Abdominal aortic plexus
Celiac plexus, superior mesenteric plexus and inferior mesenteric plexus
Hypogastric plexus
Supplies pelvic viscera
(Vagina, penis, clitoris, bladder and uterus)
Autonomic reflexes
Maintain homeostasis
-smooth muscles contractions
-cardiac muscle contractions
-gland secretion
Receptors that bind ACh are called
Cholinergic receptors
