Exam #6 Chapter 15 Flashcards
- regulates cardiac muscle, smooth muscle, and glands (visceral effectors: internal organs)
- system operates subconsciously, you cannot control its effectors
autonomic nervous system (ANS)
- system receives input from interoceptors
- like the motor half of the system, most visceral sensations are not perceived
- ex: CO2
ANS
-sensory receptors located in blood vessels, visceral organs, muscles, and the nervous system that monitors conditions in the internal environment
interoceptors
- most effectors of the ANS have dual innervation from both the ______ and ______ divisions
- typically these systems have opposite effects, fight or flight vs rest and digest
sympathetic and parasympathetic
-third division of the ANS, millions of neurons in GI tract
enteric nervous system
-in somatic nervous system, a single axon extends from the _____ to ______
central nervous system to effector
-in the ANS, there are two neurons in series. One myelinated axon from the ______ to ______, and one unmyelinated from the ______ to ______
CNS to ganglion
ganglion to effector
-alternatively, CNS connects to ______ in adrenal gland
chromaffin cell
- cell body in brain/SC, axons are cranial/spinal nerves
- myelinated, synapses with postganglionic neurons
preganglionic neuron
- part of the PNS
- location of cell bodies and dendrites of postganglionic neurons
automatic ganglion
- named for the fact that the axons extend from the ganglion
- their cell bodies actually form the ganglion
- unmyelinated, synapses with effectors
postganglionic neurons
-sensory input is from somatic senses and special senses
somatic nervous system
-control of motor output: voluntary control from cerebral cortex, with contributions from basal ganglia, cerebellum, brainstem, and spinal cord
somatic nervous system
-motor neuron pathway: one neuron pathway, somatic motor neurons extending from CNS synapse directly with effector
somatic nervous system
-neurotransmitters and hormones: all somatic motor neurons release only ACh
somatic nervous system
- effectors: skeletal muscle
- responses: contraction of skeletal muscle
somatic nervous system
-sensory input: mainly from interoceptors, some from somatic senses and special senses
autonomic nervous system
- control of motor output: involuntary control from hypothalamus, limbic system, brainstem, and spinal cord
- limited control from cerebral cortex
autonomic nervous system
- motor neuron pathway: usually two pathways, preganglionic and postganglionic
- preganglionic neurons may extend from CNS to synapse with chromaffin cells of adrenal medullae
autonomic nervous system
- neurotransmitters and hormones: all sympathetic and parasympathetic preganglionic neurons release ACh
- most sympathetic postganglionic neurons release NE, those to most sweat glands release ACh
- all parasympathetic postganglionic neurons release ACh
- chromaffin cells of adrenal medullae release epinephrine and norepinephrine
autonomic nervous system
- effectors: smooth muscle, cardiac muscle, and glands
- responses: contraction or relaxation of smooth muscle, increase and decreased rate and force of contraction of cardiac muscle, increased and decreased secretions of glands
autonomic nervous system
- cell bodies located in T1-12 and L1-3
- also named the thoracolumbar division, and the axons are the thoracolumbar outflow
outflow of the sympathetic autonomic nervous system (S-ANS)
- big strip of ganglia from the skull to the coccyx
- those in the head/neck have specific names
sympathetic trunk ganglia (STG)
S-ANS
-muscles of the face, glands of head, and heart: _______ cervical ganglion
superior
S-ANS
-the heart: ______ cervical ganglion
middle
S-ANS
-cardiac and pulmonary plexuses: _______ cervical ganglion
inferior
S-ANS
-_______ have longer preganglionic axons
parasympathetic division
S-ANS
-the splanchnic nerves are ______
pre-ganglionic
S-ANS
-connects to the celiac ganglion
greater splanchnic nerve
S-ANS
-innervates with the liver, GB, stomach, spleen, and pancreas
celiac ganglion
S-ANS
-connects do aorticorenal ganglion: the kidneys and ureter
lesser splanchnic nerve
S-ANS
-connects to renal ganglion, kidney, and ureter
least splanchnic nerve
S-ANS
-innervates the intestines
superior mesenteric ganglion
S-ANS
-synapses in the inferior mesenteric ganglion
lumbar splanchnic nerve
S-ANS
-innervates rectum and colon
inferior mesenteric ganglion
S-ANS
-innervates bladder, genitals, and uterus
hypogastric plexus
S-ANS
- axon may synapse with the first neuron it reaches
- axon may ascend/descend to a different ganglion (can form plexuses)
- axon may continue through the STG without synapsing to the prevertebral ganglion
- axon may pass through both to synapse with chromaffin cell in adrenal gland
how neurons connect in ganglia
S-ANS
- cell bodies in the brainstem nuclei (cranial nerves III, VII, IX, X) and S2-S4
- also known as the craniosacral division, and the axons are the craniosacral outflow
outflow of the parasympathetic autonomic nervous system (PS-ANS)
-synapses in the ciliary ganglion, then onto smooth muscles of the eye
CN III
PS-ANS
-has axons in both the ptergopalatine ganglion (lacrimal glands, nasal mucosa) and the submandibular ganglion (salivary glands)
CN VII
PS-ANS
-synapses at the otic ganglion, innervates parotid salivary glands
CN IX
PS-ANS
- axons carry 80% of the total craniosacral outflow
- there are many terminal ganglia throughout the thorax and abdomen
vagus X
PS-ANS
-extend to terminal ganglia in the walls of the colon, ureters, bladder, reproductive organs
pelvic splanchnic nerve
PS-ANS
-release the NT acetylcholine
•all sympathetic and parasympathetic preganglionic neurons
•sympathetic postganglionic neurons to sweat glands
•all parasympathetic postganglionic neurons
**every neuron except most sympathetic postganglionic neurons
cholinergic neurons
two types of cholinergic receptors
nicotinic and muscarinic
-named because nicotine can bind to the ACh receptors
nicotinic
-named for the mushroom poison muscarine
muscarinic
-integral proteins in postsynaptic plasma membranes, activated by ACh
cholinergic
- in plasma membrane of postganglionic sympathetic and parasympathetic neurons: excitation—>impulses in postganglionic neurons
- in chromaffin cells of adrenal medullae: epinephrine and norepinephrine secretion
- in sarcolemma of skeletal muscle fibers (motor end plate): excitation—>contraction
nicotinic
- in effectors innervated by parasympathetic postganglionic neurons: in some receptors, excitation, in others, inhibition
- in sweat glands innervated by cholinergic sympathetic postganglionic neurons: increased sweating
- in skeletal muscle blood vessels innervated by cholinergic sympathetic postganglionic neurons: inhibition—>relaxation—>vasodilation
muscarinic
-cholinergic neurons release ______
ACh
-receptors for neurotransmitters are found on the surface of ______
post-synaptic cells
-______ inactivates ACh, so the effects of ______ neurons are brief
ACh-ase
cholinergic
- _______ neurons release norepinephrine (NE), also called noradrenaline
- these neurons are most postganglionic neurons
adrenergic
-adrenergic receptors bind both ______ and ______
norepinephrine and epinephrine
- norepinephrine may be released as a ______ or a ______
- epinephrine is always released as a ______
neurotransmitter, hormone
hormone
-activity of norepinephrine last longer than ACh, until re-uptake, or inactivated by _______ or _______
catechism-O-methyltransferase (COMT) or monoamine oxidase (MO)
- a1 and b1 receptors produce ______
- a2 and b2 receptors cause ______
- b3 receptors are only found in ______ and cause heat production
excitation
inhibition
brown adipose tissue
- neurons ______
- effectors _____
secrete, bind
-smooth muscle fibers in blood vessels serve salivary glands, skin mucosal membranes, kidneys, and abdominal viscera, radial muscle in iris, sphincter muscles is stomach and urinary bladder
•excitation—>contraction causes vasoconstriction, dilation if pupil, and closing sphincters
-salivary glands cells
•secretion of K+ and water
-sweat glands on palms and soles
•increased sweating
a1
-a1, a2, b1, b2, and b3 are _______
adrenergic
-smooth muscle fibers in some blood vessels
•inhibition—>relaxation—>vasodilation
-cells of pancreatic islets that secrete the hormone insulin ( beta cells)
•decreased insulin secretion
-pancreatic acinar cells
•inhibition of digestive enzyme secretion
-platelets in blood
•aggregation to form platelet plug
a2
-cardiac muscle fibers
•excitation—>increased force and rate of contraction
-juxtaglomerular cells of kidneys
•renin secretion
-posterior pituitary
•antidiuretic hormone (ADH) secretion
-adipose cells
•breakdown of triglycerides—>release of fatty acids into blood
b1
-smooth muscle in walls of airways, in blood vessels that serve heart, skeletal muscle, adipose tissue, and liver, and in walls of visceral organs, such as urinary bladder
•inhibition—>relaxation, which causes dilation it airways, vasodilation, and relaxation of organs walls
-ciliary muscle in eye
•inhibition—>relaxation
-hepatocytes in liver
•glycogenolysis (breakdown of glycogen into glucose)
b2
-brown adipose tissue
•thermogenesis (heat production)
b3
-bind to and activate receptors, like we described with nicotine and muscarine, the intended signaling molecule is ACh but the others act as _______
agonists
- are the opposite, they bind and block activation
- example is the Beta blocker, named for the b1 receptors they bind to, decreasing heart rate and blood pressure
antagonist
- most effectors receive innervation from both the sympathetic and parasympathetic branches of the ANS, which oppose each other
- the balance between their activity is called ______
autonomic tone
-the ______ regulates the autonomic tone , increasing one branch and decreasing the other when needed
hypothalamus
-some structures are \_\_\_\_\_\_ only like: •sweat glands •arrector pili muscles •kidneys •spleen •blood vessels •adrenal medullae
sympathetic
- active during physical or emotional stress, it’s _____ to what’s happening to you
- high S-tone allows for vigorous activity and consumption of _____, downregulating activities that store energy, also reacts to emotions: fear, embarrassment, excitement, rage
- think of “E situations”, exercise, emergency, excitement, embarrassment
sympathetic
ATP
-activating the S-ANS and releasing adrenal hormones leads to a set of responses called ______
fight or flight response
-_______ has the following effects:
•pupils dilate
•heart rate, force of contraction, BP increase
•airways dilate
•blood vessels that apply kidney and GI tract constrict, decreasing urine production and digestion
•blood vessels supplying skeletal and cardiac muscles, kidneys and adipose tissues dilate
•livers cells perform glycogenesis (increasing blood glucose), adipose tissues from lipolysis
•decrease of non-essential activities, such as GI tract and digestive enzymes
fight or flight
- ______ responses are all about rest and recovery (digest)
- SLUDD*
- salivation
- lacrimation
- urination
- digestion
- defecation
-also the 3 decreases:
•decrease in heart rate
•decrease airway radius (bronchocontriction)
•decreased diameter of the pupils (construction)
parasympathetic
