ions
what is an ion?
An ion is an electrically charged molecule
action potential is ____ or _____
all or nothing
Acetylcholine was the ____ neurotransmitter to be discovered
first
what is the difference between an agonist and an antagonist?
Agonist= a molecule that acts like the neurotransmitter meant for that receptor. Makes the receptor think the neurotransmitter is actually present
Antagonist= molecule that blocks the binding of a transmitter to a receptor
what is an electrostatic gradient?
an area where there is an unequal distribution of pos/neg ions.
what is the refractory period
time needed to recovery between action potentials.
what does acetylcholine do when it binds to a receptor?
it allows sodium ions to flow into the membrane
what is the difference between degradation and reuptake?
degradation= breaking down a neurotransmitter
which side of the membrane is more negative?
The inside of the membrane
The neuron is trying to reach a _____ when sending an action potential
threshold
Is acetylcholine inhibitory, excitatory, or both.
Both excitatory and inhibitory.
what is the most plentiful excitatory neurotransmitter?
Glutamate.
which ion sets up the membrane potential?
potassium
what is the difference between absolute and relative refractory periods?
absolute means the neuron cannot fire another action potential regardless of stimulus strength, while relative can fire another action potential if the stimulus is strong enough.
What are the two acetylcholine receptors and what are their functions?
Nicotinic= Ligand-gated ion channel. Very fast.
Muscarinic= G-protein coupled receptor. Acts through the release of a 2nd messenger. Slower, but there’s more that this receptor can do.
what are the two main pathways for dopamine?
mesostriatal= from midbrain to the striatum
Mesolimbocortical= from midbrain to nucleus accumbens, cortex, and hippocampus
why is water important for ions?
If you don’t have water, you have no way to keep ions separate from each other
what is the difference between excitation and inhibition?
excitation is depolarizing the cell while inhibition is hyperpolarizing it.
what is acetylcholine released by?
Released by parasympathetic ganglion neurons, motor neurons, etc.
Where is norepinephrine released from?
Released by locus coeruleus