Chapter 1- Nervous System Flashcards
the autonomic nervous system is located in the
visceral motor division of the peripheral nervous system
visceral
internal body
somatic
external body
sympathetic nervous system helps
prepare for action
parasympathetic nervous system helps
with calming
autonomic NS innervates
glands, cardiac muscle, smooth muscle
automatic NS control is
involuntary
the result of loss of ANS innervation
structures still function, denervation hypersensitivity
denervation hypersensitivity
smooth and cardiac muscle becomes hyperactive
somatic NS innervates
skeletal muscle
somatic NS control is
voluntary
result of loss of SNS innervation
muscle can’t function, atrophy
sympathetic and parasympathetic visceral motor function has what affects
opposite effects on innervated structure
Sympathetic and Parasympathetic HR function
increase, decrease
sympathetic and parasympathetic respiratory function
bronchodilation (increase), bronchoconstriction (decrease)
sympathetic and parasympathetic direct blood flow to
skeletal muscle, digestive and urinary system
sympathetic and parasympathetic salivary and lacrimal gland function
decrease secretion, increase secretion
sympathetic and parasympathetic sweat gland function
increase secretion, decrease secretion
somatic motor fibers begin
in the spinal cord or brainstem
somatic motor fibers are many/one throughout the body
single axon from origin to target organ
autonomic motor pathway
nerve signal, preganglionic neuron, postganglionic neuron
nerve signals in the autonomic motor pathway travel across one/two/many neurons to reach target
one
preganglionic neuron
neuron in amp that is located in the brain/spinal cord
postganglionic neuron
neuron in amp that is innervates the target organ
how many ANS neurons synapse at the autonomic ganglion
two
ganglion
collection of cell bodies in the PNS
sympathetic ganglion are close/far from the target organ
far
parasympathetic ganglion are close/far from the target organ
close/on the target cell
the sympathetic division is also called the
thoracolumbar division
preganglionic cell bodies in the SNS are found in what part of the vertebrae
lateral horn
preganglionic cell bodies in the SNS are found in what sections of the spinal cord
thoracic and lumbar
sympathetic ganglia are found in the
sympathetic chains of ganglia
other names for the sympathetic chains of ganglia
sympathetic chains, sympathetic chain ganglia, sympathetic trunks
sympathetic chains of ganglia are
nervous tissue structures on either side of the spinal cord containing ganglia and preganglionic axons
sympathetic ganglia outside of the sympathetic chain are called
collateral ganglia
preganglionic axons of the SNS are long/short, postganglionic fibers are long/short
short, long
adrenal glands location
superior to the kidney
layers of the adrenal gland from outer to inner
adrenal cortex, adrenal medulla
adrenal cortex
outer layer that secretes steroids
adrenal medulla
inner layer that secretes catecholamines
catecholamines
adrenaline and noradrenaline
the adrenal medulla is innervated by
preganglionic sympathetic fibers
the preganglionic sympathetic fibers in the adrenal medulla are made of
modified postganglionic neurons with no axons
the neurosomas of the adrenal glands secrete
hormones directly into the bloodstream
importance of adrenal gland hormone secretion
same effect as SNS
increases the number of cells affected by SNS
increases length of SNS activity
The parasympathetic division is also called the
craniosacral division
cell bodies of the Parasympathetic division are located in
the brainstem and sacral spinal cord
the PSNS travel through
Cranial Nerves III, VII, IX, V
sacral spinal nerves
most important cranial nerve of the PSNS
vagus (X)
preganglionic fibers of the PSNS are long/short, postganglionic fibers of the PSNS are long/short
long, short
terminal ganglia of the PSNS are found
in/near the target organ
autonomic effects of PSNS and SNS are different because
use different neurotransmitters
neurotransmitter can have different effect on a different receptor
some target cells are only innervated by the PSNS or SNS
neurotransmitters in preganglionic fibers
acetylcholine
neurotransmitters in postganglionic fibers
SNS: norepinephrine or ACh
PSNS: ACh
cholinergic Recptors bind to
ACh
nicotinic receptors are found on all
postganglionic neurons
nicotinic receptors are found on what specific target organ
adrenal medulla
nicotinic receptors are excitatory/inhibitory
excitatory
muscarinic receptors are found on
target cells
muscarinic receptors are excitatory/inhibitory
both
adrenergic receptors bind to
norepinephrine
adrenergic receptors are found
on all target cells
alpha adrenergic receptors are excitatory/inhibitory
excitatory
beta adrenergic receptors are excitatory/inhibitory
inhibitory
dual innervation
innervated by both PSNS and SNS fibers
what target organs are not dually innervated? only the SNS
blood vessels, sweat glands, adrenal medulla
autonomic tone
baseline level of sympathetic and parasympathetic stimulation of effectors
sympathetic stimulation of target cells is adjusted by
increasing/decreasing rate of APs fired
example of adjusting sympathetic stimulation of blood vessels
more APs = more constriction of vessels
Less APs = less constriction of vessels
enteric nervous system
NS of the digestive tract
Enteric NS is independent/dependent of other NS
independent, not connected
smooth muscle and glands in the digestive tract are innervated by
the enteric NS and the autonomic NS
normal function of the digestive tract requires/does not require ENS and ANS innervations
does not require
