are and 4. Calculate amplitude of action potential, if concentrations of potassium and sodium inside the neuron ck = 125 mmole/liter, cm = 1.5 mmole/liter, outside CK = 2.5 mmole/liter, Cena = 125 mmole/liter respectively. Suppose diffusion temperature T = 20C. 5. Assume that frog muscle cell membrane is permeable to Na and K only. The membrane permeabilities for Na and K are Pk and Pna, respectively. At 18C the resting membrane potential is AV = -85 mV. What is ratio of permeability PR / PNa? Suppose that Ch = 124 mmole/liter, chut = 2.2 mmole/liter and Cina = 4 mmole/liter, coa = 109 mmole/liter. out