SubFUN2/membrane potential Flashcards
integral membrane proteins are _______ and extrinsic membrane proteins are ______
integral, extrinsic
______ mols can go through PM and _____ mols cant go through PM
nonpolar, polar
magnitude of plasma membrane potential depends on the degree of ________ separation
charge separation
cell membrane is more _____ inside than outside
negative
2 things that are responsible for RMP
- unequal distribution of K+, Na+ and A- b/w inside and outside of cell
(K+ and A- = ICF)
(Na+ = ECF)
- selective leakiness of PM to K+
K+ ECF/ICF
5/150 (mM)
Na+ ECF/ICF
150/15 (mM)
A- ECF/ICF
0/65 (mM)
___ Na+ ____, and ___ K+ ___
3, out, 2, in
at RMP, the inside becomes a little negatively charged because of the _______ transport of positive ions.
unequal, 3+ out and 2+ in
this only generates a small part of the potential diff though.
diffusion of __ out of the cell down conc. grad., est. by pump, is responsible for most of the potential. it leaves the inside more _____
K+, negative
2 membrane constituents that give neg. charge to inner membrane
PIP2 and PS
______ gradient acts as driving force for diff. of K+ out of the cell
chemical
the neg. charge inside acts as an ______ driving force drawing K+ back into the cell
electrical
equilibrium is when there is no ____ transport
net
nernst equation
e = 61 x log (Co/Ci)
is the PM permeable to Na+
yes, very! cause the Na+ on the outside wants to get to the negative inside
The RMP is always close to the ______ equilibrium potential
potassium
if the membrane becomes permeable to another ion, it will move ______ its equilbrium potential
towards
2 types of co transporters
[na+ - glucose co-transporter] (SGLT), and [Na+ -amino acid co-transporter]
exchangers
Na+ - Ca2+ exchanger and Na-H+ exchanger
3 classes of ion channels and ex.
leak channels (K+), voltage gated channel (VGSC), ligand gated channel (AChe receptor)
selectivity filters on ion channels
pore diameter, shape, electric charge along the pore
types of gating in ion channels
voltage, ligand/chemical, mechanical, phosphorylation
ex. of drugs changing voltage sensitive ion channels
local anaesthetics and Ca2+ channel blockers
