Nervous System Flashcards
basic unit of nervous system
neuron
dendrite part of neuron
short branches off of cell body/cyton they receive signals
cell body/cyton
contains the organelles of the neuron and does the metabolic activities
axon
long fiber that connects the cell body
to the terminal branches
schwann cells
produce myelin
myelin
fatty insulation on the axon
nodes of ranvier
space in between schwann cells/mylin on axon
multiple sclerosis
immune system attacks your mylin
terminal branches
send signals from the axon to the synaptic knobs
synaptic knobs
the electrical signal causes the release of neurotransmitters from vesicles
synapse
space between two neurons
types of neurons
~sensory neurons
~interneurons
~motor neurons
sensory neurons
send messages from receptors to the brain and spinal cord
interneurons/associative neurons
relay messages from neuron to neuron (very short)
motor neurons
send messages from brain and spinal cord to effectors
effectors
muscles and glands
receptors
eyes, ears, mouth, nose, skin
nerves
bundles or neurons
charges of a neuron at rest
outside = positive
inside = negative
when a membrane is polarized
it is separated
sodium-potassium pump
pumps potassium into the cell and sodium out of the cell
stimulus
an outside factor that causes an impulse
ex. light, heat, sound, pain
stimulus
an outside factor that causes an impulse
ex. light, heat, sound, pain
path of an impulse
a stimulus causes a receptor to produce an impulse that goes to the brain to produce a response
action potential
wave of depolarization and re polarization along the neuron
depolarization
sodium gates open when there is enough stimulus and positively charged sodium goes into the cell (cell becomes positive inside negative outside) then the potassium gates open and the positive potassium leaves (repolarization, cell becomes negative)