Partial preview of the text
Download Overview of Peripheral Nervous System: Nerves, Neurons, and Neuroglia and more Quizzes Physiology in PDF only on Docsity!
Nervous system overview
Master ControlAided byEndocrineSystemMonitor Outside
bodySensory Input-gathersIntegration-processingMotor
Output-Action
TERM 2
Central Nervous System Parts
DEFINITION 2
BrainSpinal Cord
TERM 3
Central Nervous System Function
DEFINITION 3
IntegrateandCoordinateIntelligence, memory, and emotion
(higher function)
TERM 4
Peripheral Nervous System
DEFINITION 4
Neural tissue outside the CNSNerves Extending off the brain
and spinal cord1. Carry impulses to and away from the
centralnervoussystem2. Serve as communication
linesAccessory structures ( sensory organs)
TERM 5
Two subdivisions of PNS
DEFINITION 5
AfferentEfferent
Afferent
Impulses arriving at the brain from the sensory neurons
TERM 7
Efferent
DEFINITION 7
Impulses going away from the brain, motor neuron, either
muscle or glands
TERM 8
Somatic Nervous System
DEFINITION 8
The somatic nervous system is the part of the peripheral
nervous system associated with the control of body
movements via skeletal muscles. The SoNS consists of
efferent nerves responsible for stimulating muscle
contraction, including all the non-sensory neurons connected
with skeletal muscles and skin.Voluntary
TERM 9
Autonomic Nervous System
DEFINITION 9
The autonomic nervous system is the part of the peripheral
nervous system that acts as a control system functioning
largely below the level of consciousness, and controls
visceral functions. Involuntary
TERM 10
Sypathetic
DEFINITION 10
Fight or Flight,Fast skeletal Movement, Reflexes
Neuron Cell Body
Soma ( containsNucleusand most oforganelles)
TERM 17
Neuron Dendrites
DEFINITION 17
Carry Impulses toward the cell bodyTOWARDmultiple
Dendrites
TERM 18
Neuron Axons
DEFINITION 18
AWAYCarry's impulses away from the cell body, one per cell1.
Electrical impulses2. Axon Branches tosynapticor terminal ends3.
When an impulse arrives at the synaptic knob the impulse
stimulates a chemical to be released into the extra cellular space
the synaptic cleft.4. Synaptic Cleft, space between the nob and
the cellBecause of the synaptic cleft neurons do not touch
TERM 19
Antegrade Movement
DEFINITION 19
Molecule movement from the cell body out of the axon
TERM 20
Retrograde movement
DEFINITION 20
movement in other microtubules toward the cell body
Virus and Bacterial Toxins
If they are attacking the nervous tissues can use these
pathways to invade the neuron. Examples include Rabies,
polio, herpes simplex, tetanus. They will travel the
retrograde part.
TERM 22
Myelin Sheath
DEFINITION 22
Fatty white substance that insulates that process
TERM 23
Node of renvier
DEFINITION 23
Gap, junction between one node to the next
TERM 24
Multiple Sclerosis
DEFINITION 24
Is a disease that destroys the myelin
TERM 25
Differences between the CNS and PNS
DEFINITION 25
Cell Body - CNS=Nucli PNS = GangliaNeuron Processes -
CNS= tracts PNS = NervesCns area of myelinated cells -
white matter, areas of unmylinated fibers- gray matter
Higher level functions of sensory
neurons
Sight, taste, hearing, smell, touch, andequilibrium
TERM 32
Motor Neurons
DEFINITION 32
Effort, carry instructions from the CNS to the peripheral
tissues. Cell bodies are located in the CNS
TERM 33
Two divisions of motor neurons
DEFINITION 33
Somatic-voluntarycontrolAutonomic -involuntary
TERM 34
Interneurons
DEFINITION 34
Entirely inside the CNS, connect nuerons
TERM 35
Neuroglia cell
Funtions
DEFINITION 35
Nutrition for neuronmyolinsheathsupport insulate and
protectsmall and greatly out number the neurons
Neuroglia Types
Astrocytes- nutrition to neurons, nook up to blood vessels,
blood is toxic to nerve cellsMicroglia- phygocytesEpendymal -
circulatescerebralspinal fluid, cushions the
CNSOgliodendrocytes- myolin sheath on neurons in
CNSSchwann Cells -Myolin sheath in the PNS
TERM 37
Classification of Neurons
DEFINITION 37
Structural- based on physical make upUnipolar- single
process from the cell body ( sensory Neurons)Bipolar- Two
Process from the cell body ( special senses)Multipolar -
multiple process from the cell body ( motor neurons)
TERM 38
Irritablility
DEFINITION 38
ability to respond to stimulus and convert to impulse
TERM 39
Conductivity
DEFINITION 39
Move impulses the entire length of neuron
TERM 40
Impulses are?
DEFINITION 40
Electrical, potential energy that drives the impulses
Three important changes occur in action
potential
Resting statedepolarizationrepolarization
TERM 47
Propagation of the action potential
DEFINITION 47
rapid movement of the action potential along the entire
length of the membraneonce it starts it goes all the way
TERM 48
Refractory period
DEFINITION 48
period ofunresponsiveness, can not respond to another nerve
stimulus
TERM 49
unmyelinated nerve fiber
DEFINITION 49
domino effect, continual conduction
TERM 50
Myelinated sheathes
DEFINITION 50
conduct really fast, saltatory
Multiple Sclerosis
Destroys myolin sheath
TERM 52
conduction velocity-
DEFINITION 52
Nerve conduction velocity is the speed at which an
electrochemical signal propagates down a neural pathway.
TERM 53
synapse
DEFINITION 53
In the nervous system, a synapse is a structure that permits
a neuron to pass an electrical or chemical signal to another
cell (neural or otherwise). Gap
TERM 54
Electrical Synapses
DEFINITION 54
Spark goesacross- very uncommon
TERM 55
Chemical Synapses
DEFINITION 55
Action potential reaches synaptic terminalCalcium channels
openneurotransmitter is released
intosynapsesneurotransmitter binds to post
synapticreceptorsion channels open on the post synaptic
sideaction potential travels down to the nextneurotransmitter
effectsreabsorbedby the pre-synaptic side
Diverging circuits
one incoming fiber triggers response in multiple
TERM 62
Converging Circuits
DEFINITION 62
several stimulus focused on one spot
TERM 63
Reflex Arc
DEFINITION 63
a neural pathway a reflex travels
TERM 64
Four minimum components of all reflex arcs
DEFINITION 64
sensory receptor - reacts to stimulusafferent neuron- takes
to CNSefferent neuron - motor neuroneffector organ- muscle
or glandMinimum number of neurons in an arc is 2afferent --
> efferentmore complex have threeafferent--> interneuron---
> efferent
TERM 65
CNS
DEFINITION 65
groups of neuron cell body in in CNS = centers, in PNS=
Gangliabundles of axons in CNS= tracts in PNS = Nerves
Spinal Cord
major highway for sensory impulses to the brain and motor
impulses from the brain. and is involved in its own reflexes
(spinal reflexes) These include withdraw from pain, siting,
standing, walking, and running.Exits from the magnum
foramenHas 31 pairs of spinal nervesis covered inmeninges
TERM 67
Meningitis
DEFINITION 67
Meningitis is inflammation of the protective membranes
covering the brain and spinal cord, known collectively as the
meninges.
TERM 68
Gray Matter
DEFINITION 68
Grey matter is a major component of the central nervous
system, consisting of neuronal cell bodies, neuropil
(dendrites and unmyelinated axons), glial cells (astroglia and
oligodendrocytes) and capillaries. Located in the middle
TERM 69
White matter
DEFINITION 69
White matter is one of the two components of the central
nervous system and consists mostly of glial cells and
myelinated axons that transmit signals from one region of
the cerebrum to another and between the cerebrum and
lower brain centers.
TERM 70
Three directions of white matter
DEFINITION 70
afferent - sensoryefferent - motorcommissural branch'sthat
connect afferent to efferent
Temporal Lobe
smell, auditory, speech comprehension, tells about sounds
and smells
TERM 77
Occipital Lobe
DEFINITION 77
sight, shape recognition, patterns
TERM 78
Corpus Callosum
DEFINITION 78
bridges left and right hemispheres of brain
TERM 79
Problems with Basal ganglia
DEFINITION 79
parkinsons diseases - lack of neurotransmitter dopamine, can
not initiate motor activityHuntingtons Chorea - inability to
control muscles, treatments include drugs that block
dopamine
TERM 80
Diencephalaon
DEFINITION 80
Inner brain, on top of brain stem, inferior to corpus callosum
Thalamus
upper part of the diencephalon, relay station for incoming
impulses
TERM 82
hypothalamus
DEFINITION 82
lower part , autonomic nervous system, reflex, makes
horomonesregulates body temp, water balance, level of
metabolismcenter for , many drives, emotion, thirst,
appetite, pain, pleasure, sex
TERM 83
pituitary gland
DEFINITION 83
major endocrine organ
TERM 84
Mamillary bodies
DEFINITION 84
reflex center for smell...
TERM 85
cerebral peduncles
DEFINITION 85
motor tracks going though spinal cord, fight or flight
response, sympathetic startle reflex, eye hand coordination.
Medulla oblongata
inferior part of the brain stem, control autonomic functions
TERM 92
Cerebellum
DEFINITION 92
The cerebellum is a region of the brain that plays an
important role in motor control.
TERM 93
Menigies
DEFINITION 93
covering for spine and brainDura mater-
itsdurableAnachnoid- web like fibers that bind together, CSF
flows herePia Mater- delicate ( inflamation= meningitis )
TERM 94
CSF and ventricles
DEFINITION 94
located around sub- arachnoid spaceventriclesfunction-
cushionthe brain, makes the brain float better
TERM 95
CSF movement
DEFINITION 95
choroid plexus, lateral ventricles, foramen monroe, third
ventricle, cerebral aqueduct to forth ventrical though central
canal, and out into the bubarachnoid space and over the
surface of the spinal cord, cerebellum and cerebrum.
hydrocephalus
Hydrocephalus, also known as "water in the brain," is a
medical condition in which there is an abnormal
accumulation of cerebrospinal fluid (CSF) in the ventricles, or
cavities, of the brain. will result in brain damage
TERM 97
Peripheral nerves
DEFINITION 97
any nerve branching off of the CNS
TERM 98
Cranial Nerves
DEFINITION 98
Directly off the brain (12 pair)
TERM 99
Spinal Nerves
DEFINITION 99
cervical,thoracic, lumbar31 pair
TERM 100
Nerve Plexuses
DEFINITION 100
where nerves converge and travel in a common passageway
