Biological Basis - Neurons/Neurotransmitters Flashcards
Neuron
basic cell of the nervous system
Dendrites
receive incoming signal
soma
cell body
axon
action potential travels down it
Myelin Sheath
speeds up the action potential down the axon, protects the axon, attacked by Tcells
Axon Terminals
release neurotransmitters, sending the signal to the next neuron
Vesicles
sacs inside the terminal that contain neurotransmitters
Synapse
gap between neurons
Action Potential
movement of Sodium and Potassium ions across the membrane
what does action potential do
sends an electrical charge down the axon
all or none law
stimulus must trigger the action potential past its threshold, but does not increase the intensity of the response
(flush the toilet)
refractory period
neuron must rest and reset before it can send another action potential
(toilet resets)
Sensory neurons
receives signals
Afferent neurons
Accept signals
Motor neurons
sends signals
Efferent neurons
signal Exits
interneurons
cells in spinal cord responsible for reflex loop
Sympathetic Nervous System
arouses the body’s fight/flight response (generally activates– sympathetic to you getting eaten by a tiger so it helps you run away)
Parasympathetic Nervous System
established homeostasis after a sympathetic response (generally inhibits)
Neurotransmitters (NT)
chemicals released in synaptic gap, received by neurons
GABA
major inhibitory neurotransmitter
GlutamatE
major Exitatory neurotransmitter (get excited when seeing your mates!)
Dopamine
reward & movement
Serotonin
moods & emotion
Acetylcholine (ACh)
memory (neurotransmitter)
Epinephrine & Norepinephrine
sympathetic nervous system arousal
Endorphins
pain control
Oxytocin
love and bonding
Agonist
drug that mimics a neurotransmitter
Antagonist
drug that blocks a neurotransmitter
Reuptake
unused neurotransmitters are taken back up into the sending neuron. SSRIs block reuptake, hence treating depression
SSRI
selective serotonin reuptake inhibitors
