Excitability, membrane potential, diffusion, ohm's law

membrane potential

voltage across the neuronal membrane at any moment

Distribution of Ions

potassium (k+) more concentrated inside, sodium, calcium, chloride more concentrated outside

action potential

brief fluctuation in membrane potential caused by rapid opening &closing of voltage-gated ion channels - don’t diminish over time

cells capable of generating & conducting action potential have an…

excitatory membrane

excitatory membrane

any membrane capable of generating action potentials, membrane of axons & muscle cells are excitable

resting membrane potential

membrane potential (membrane voltage) maintained by a cell when not generating action potentials, neurons have around -65mV resting potential

concentration gradient

rate of movement of electrical charge, measured in ohms

electrical potential

voltage different between the endolymph and perilymph, ~80mV

voltage

force exerted by an electrically charged particle, represented by V & measured in volts

electrical conductance

relative ability of an electrical charge to migrate from one point to another, represented by g & measured in siemens

electrical resistance

relative inability of an electrical charge to migrate from one point to another, represented by R & measured in ohms

ohm’s law

relationship between electrical current (I), voltage (V) & conductance (g)

membrane potential

voltage across a cell membrane, represented by Vm

ionic equilibrium potential

the electrical potential different that exactly balances an ionic concentration gradient (E ion)

ionic driving force

difference between real membrane potential (Vm) & ionic equilibrium potential (E ion)