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24 Cards in this Set
- Front
- Back
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_= difference in charge across membrane
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membrane potential
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membrane potential results in part from _ being trapped insided a cell and action of _
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large anions
Na+/K+ pumps |
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The membrane is more permeable to _ and less permeable to _ which must pumped out
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K+
Na+ |
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_ like _, _ and _ are attracted into cell by trapped _ thus they accumulate within the cell
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K+
Na+ Ca2+ anions |
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Anions are located
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intracellularly
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The magnitude of charge difference between the inside and outside of the cell is measured in _
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voltage
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_ is attracted inside by the trapped anions but also driven out
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K+
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The electrical properties of cells is based on the difference in the _ and _ of the plasma membrane to each of these ions
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specific ions
permeability |
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_= theoretical voltage across cells membrane if only 1 ion could diffuse through the membrane
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equilibrium potential
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if membrane permeable only to_, it would diffuse until reaches _
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K+
equlibrium potential |
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K+ is attracted inside by _ but also driven out by its _
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trapped anions
gradient |
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At K+ equlibrium, electrical and diffusion forces are
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?
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-90mV means that the inside of cell has _ negative charge than the outside because at this point there is not enough _ inside to neutralize charge form the _
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more
K+ anions |
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The voltage difference across the membrane =
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potential difference
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In reality, more than _ contributes to the _. Equilibirum potential only descirbes _ across cell membrane if only 1 ion could _
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one ion
resting membrane potential IFF voltage diffuse |
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_= allows theorectical equalibrium potential to be calculated if ion are known
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Nernst equation
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_ gives membrane voltage needed to counteract concentration forces acting on an ion
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Ex
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Value of Ex depends on _
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ration of ion inside and outisde cell membrane
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_= membrane voltage of cell in unstimulated state
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RMP
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RMP of most cells is _ to _
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-65 to -85mV
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RMP depends on
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concentrations of ions inside and out
permeability of each ion |
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Affected most by _ because the membrane is most permeable to it, but some _ _ in so RMP is less negative than _
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K+
Na+ diffuses Ex |
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Because _ are pumped out for every _ taken in, pump is _
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3 Na+
2 k+ electrogenic |
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NA+/K+ adds about _ to RMP
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-3mV
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