Neuron & Synapse Flashcards
Dendrites
Short branches built to receive information
Presynaptic Terminal
Holds the vesicles of neuro transmitters
Axon
Carries information away from the neuron
Soma
Cell body
How does myelination impact propagation of an action potential
Heavier myelination = a faster conductance
What is an equillibrium potential
The membrane voltage that balances the concentration of gradient force
Ion channel
Can be opened or closed, dependent on forces to move, selective
Ion pumps
moves against gradients, USES ATP, selective
How does the nervous system code for intensity of a stimulus if an action potential is always the same size and duration
Temporal summation
Local potentials
grades in different size and duration
a larger local potential can spread farther than a smaller one
Action Potentials
Can be repeatedly regenerated along a long distance
Causes a rapid reversal of a change inside the cell
Where do local potentials happen
Modality and ligand gated channels
Lingand-gated channels
ion channels that open in response to a neurotransmiter
Where is a ligand-gated channel located
post-synaptic membrane
Spatial summation
multiple synapses occuring on a neuron at the same time
how does an increase in diameter of the axon impact propagation
creates a faster flow
Synapses can occur
Axon to dendrite
Axon to soma
Axon to axon
*ALWAYS starts with an AXON
What does the presynaptic terminal contain
Neurotransmiter vesicles
What is an IPSP
Inhibitory postsynaptic potential-
Caused by: opening of potassium channels in the post synaptic membrane
What is a NT agonist
Another chemical that has similar effect a a neurotransmitter
(opens receptor)
What is a major source of inhibition in the CNS
GABA- Valium, BACLOFEN, phenobarbital
What is depolarization
A brief change were the inside of the cell becomes less negative and more excitable
Hyperpolarization
A brief change where the inside of the cell become more negative and more INHIBITORY
What is an EPSP
Excitatory Postsyaptic Potential- causes a muscle contraction- small depolorization of membrane.
