Ch. 6 - Membrane Potential Flashcards
charge separation across lipid bilayer gives rise to blank
membrane potential
separation of charge is maintained by blank which is a barrier to diffusion of ions, thus maintaining blank
lipid bilayer, resting membrane potential
blank is defined as a net movement of positive charge
current
there is no net flow ions in a blank cell at rest
nerve
when there is net flow cations or anions, the blank is disturbed
electric potential
a reduction or reversal of charge separation, leading to a les negative membrane potential is called blank
depolarization
blank is when the membrane potential becomes very negative
hyperpolarization
changes in the membrane potential that do not lead to the opening of gated ion channels are called blank potentials
electrotonic
when depolarization approaches a critical level, or threshold, a cell responds actively with the opening of voltage gated ion channels, which makes a blank
action potential
when a cell membrane is blank to a certain voltage, an action potential forms
depolarized
the ease with which ions can cross cell membrane
permeability
there is a blank distribution of ions inside and outside the cell
uneven
only potassium ions can pass through these cells
glial
relative proportions of various ion channels that are open
permeability
this is reached when rate of influx/efflux of potassium ions are the same
equilibrium
a function of conc gradient across the membrane
chemical driving force
a function of electrical potential difference across the membrane
electrical driving force
two forces that drive ions across the cell membrane
chemical/electrical driving forces
outward movement of potassium ions are driven by blank
conc gradient
inward movement of potassium ions is driven by blank
electrical potential difference
there are more blank than blank channels
potassium, sodium
potassium conductance is blank than sodium conductance
higher
ion flux equation]
total driving force x g (conductance)
LOWk+g(high) = HIGHna+g(low)
steady state
energy of atp hydrolysis to transport ions against conc gradient type of transport
primary active transport
transport that moves one ion against gradient by using the energy stored in the electrochemical gradient of a second ion
secondary active transport
sodium potassium pump and calcium pump are both blank transport
primary active
sodium calcium exchanger is a blank secondary active transporter
antiporter
K+ Cl- cotransporter is a blank secondary active transporter
symporter
GHK equation to find blank membrane potential
stable resting
