Neurons Flashcards
Dendrites
branchy extensions that receive messages from other cells
soma
contains nucleus and chemical machinery common to most cells
axon
passes messages away from cell body to other neurons, muscles or glands
myelin sheath
insulating material encasing axons
nodes of ranvier
gaps in myelin sheath where signal recharges
terminal buttons
small knobs secreting neurotransmitters
glial cells
makes sure neuron is clean, fed and warm
polarized state (resting potential)
positive and negative ions are separate
sodium outside
neuron is negative
depolarization (action potential)
when positives come inside
sodium inside
neuron is positive
sodium pump
removes excess sodium after it depolarizes
refractory period
cell recharges, while it recharges it cannot fire again
synapse
space between sending and receiving neurons
presynaptic neuron
sending neuron
postsynaptic neuron
receiving neuron
acetylcholine
voluntary movement
deficiencies lead to alzheimer’s
dopamine
pleasure
excess leads to schizophrenia
deficiencies lead to parkinson’s
serotonin
mood
deficiencies lead to depressive disorders
norepinephrine
alertness
deficiencies lead to depressive disorders
GABA
slows down central nervous system
deficiencies lead to anxiety disorders
glutamate
learning and memory
speeds up central nervous system
excess leads to migraines and seizures
endorphins
block pain
excess leads to euphoria
substance P
carry pain signals
excess leads to anxiety, insomnia
oxytocin
social bonding
receptor sites
each is tuned to accept only specific neurotransmitters
