Question

Lipid bi-layer of all cell membranes can be modeled as a sandwich consisting of two layers of conductors capacitor. The capacitance per unit area (specific capacitance) of cellular membranes was first determined in the 1920s to have a value of about 1 μF cm' a) State the equation that define the capaoitance of parallel-plate capacitor if a dielectric materials with dielectric permittivity ε fills the space bctwcen plates. [2 pts) b) Write the value of specific capacitance of cellular membranes in units F/m.13 pts c) Using a value of ε-, since membranes contained lipids and that oils have avalae of ε= 3, estimate the thickness of the cell membrane. [3 pts] d) Suppose the resting surface charge density 0.1 μC/cm2 and considering the time constant about 3 m. estimate the total number of Na' ions that will fnow across 1 cm of the membrane during the opening of 10 sodium channels per pum2. [4 pts]

Answer 1

/20 Date Capaulance he Caf A d u A C. Cs -12 -l o 2542 x 3 all me mhyane

sochum channel 10 13 1 2 channels rans tout,cha -12 C1 서지0~12