Search results
Results From The WOW.Com Content Network
In essence, the Goldman formula expresses the membrane potential as a weighted average of the reversal potentials for the individual ion types, weighted by permeability. (Although the membrane potential changes about 100 mV during an action potential, the concentrations of ions inside and outside the cell do not change significantly.
The calcium is taken up into the matrix by the mitochondrial calcium uniporter on the inner mitochondrial membrane. [61] It is primarily driven by the mitochondrial membrane potential. [55] Release of this calcium back into the cell's interior can occur via a sodium-calcium exchange protein or via "calcium-induced-calcium-release" pathways. [61]
The gradient also provides control of the concentration of ions such as Ca 2+ driven by the mitochondrial membrane potential. [1] The membrane only allows nonpolar molecules such as CO 2 and O 2 and small non charged polar molecules such as H 2 O to enter the matrix.
Depolarization is the process by which the membrane potential becomes less negative, facilitating the generation of an action potential. [6] For this rapid change to take place within the interior of the cell, several events must occur along the plasma membrane of the cell.
It is an active pump that generates a proton concentration gradient across the inner mitochondrial membrane, because there are more protons outside the matrix than inside. The difference in pH and electric charge (ignoring differences in buffer capacity) creates an electrochemical potential difference that works similar to that of a battery or ...
Voltage-dependent anion channels, or mitochondrial porins, are a class of porin ion channel located on the outer mitochondrial membrane. [ 1 ] [ 2 ] There is debate as to whether or not this channel is expressed in the cell surface membrane.
The structure of the inner mitochondrial membrane is extensively folded and compartmentalized. The numerous invaginations of the membrane are called cristae, separated by crista junctions from the inner boundary membrane juxtaposed to the outer membrane.
The outer membrane is porous, whereas the inner membrane restricts the movement of all molecules. The two membranes also vary in membrane potential and pH. [3] These factors play a role in the function of mitochondrial membrane transport proteins.