Nervous System Flashcards
Neuron
functional cell type
nervous system
collection of neurons that operate in a coordinated manner
dendrite
conducts an electrical signal from dendrite to axon terminal
cell body
part with nucleus
axon
long tubular extension of plasma membrane.
axon terminal
base of the axon. plasma membrane flares to create a number of sites for information transfer.
electrically excitable cell
an electrical signal can be conducted from the dendrite to the axon terminal.
polarized cell
charge changes through the cell
membrane potential
most cells are negative inside relative to the outside
depolarization
membrane potential moves from negative to positive
action potential
a wave of depolarization
hyperpolarize
membrane potential goes back to original 70
synapse
the space between two neurons
electrical synapse
cells linked by gap junctions
gap junction
space between two neurons
chemical synapse
neurotransmitter is released by exocytosis from pre-synaptic cells and opens an ion channel on the post-synaptic cell
neurotransmitter
low weight hydrophilic chemical signals. cannot move across the plasma membrane on the post-synaptic cell.
exocytosis
bubble opens to plasma membrane and neurotransmitter is released.
excitatory neurotransmitter
if the neurotransmitter causes the post-synaptic cell to depolarize
inhibitory neurotransmitter
if the neurotransmitter causes the post-synaptic cell to hyperpolarize
sensory neuron
transmits information about external stimuli as detected by sensory organs
interneuron
neurons found in circuits that are involced in the analysis and interpretation of sensory input