biopsychology: neurons and synaptic transmission Flashcards
dendrites
branch-like structures
protrude from cell body
carry nerve impulses from neighbouring neutrons towards cell body
axon
carries impulse away from cell body down the length of the neuron
meylin sheath
protects/cover the axons
speeds up electrical transmission of the impulse
why is the meylinth sheath constructed the way it is?
segmented by gaps (nodes of ranvier)
avoids reverse effect if it was continuous
speeds up as forces impulse to jump across gaps
what is at the end of an axon?
terminal buttons
what do terminal buttons do?
communicate with the next neuron in the chain across the synapse
where are motor neurons located?
cell bodies - CNS
long axons form part of PNS
where are sensory neurons located?
outside of CNS
ganglia (clusters) in PNS
where are relay neurons located?
make up 97% of all neurons
brain
visual system
what happens to a neuron in resting state
inside of cell is negatively charged compared to outside
what happens when a neuron is activated by a stimulus?
inside of cell becomes positively charged for a split second - action potential occur
what happens when an action potential occurs?
electrical impulse that travels down the axon to end of neuron
how do neurons communicate with each other?
neural networks
how are neurons separated
synapses
how are signals within neurons transmitted?
electrically
how are signals between neurons transmitted?
chemically (across synapse)
what is the end of a neuron called
presynaptic terminal
when the electrical impulse reaches the presynaptic terminal what happens
triggers release of neurotransmitters from synaptic vesicles
serotonin causes
inhibition
adrenaline causes
excitation
