Let us consider a 100-micron diameter spherical cell at room temperature with a cell membrane that...

Let us consider a 100-micron diameter spherical cell at room temperature with a cell membrane that has capacitance of one microfarad/cm2. Initially, there is no potassium in the system. However, let us introduce a potassium-anion salt into the system such that you have a concentration of 52 times more on the inside than the outside. (For this case, it is 130 mM inside and 2.5 mM outside.) Let us assume that only potassium can diffuse through the cell. At the beginning (with no salt), the membrane potential is 0 mV; however, once the salt was introduced, potassium will diffuse out such that an equilibrium potential of -100 mV is reached. How many potassium ions must diffuse out of the inside of the cell to produce a change from 0 to -100 mV?

Expert Solution

Ans: As give in the question that the capacitance is 1 microF/cm2 and the diameter of this cell is 100 micron and as we know that the area of sphere is pi*D2 and the total capacitance is 1 microF/cm2*Area.

Rest of the question is solved in the image enclosed below:

gladiator answered 2 years ago

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