Membrane Fluxes and Electric Conductance in Characean Cells

Abstract

The effects of changing the membrane potential difference (p.d.) of Ohara corallina and Nitella translucens cells on the unidirectional fluxes of potassium, sodium, and chloride ions are described. In both species, a net efflux was observed at the resting potential. Changes in net flux of potassium with p.d. amounted to 1-1·5 p-mole cm-2 sec-1 in 10 mY, contributing a partial ion conductance of about 10-15 pmho cm-2 at p.d.'s near the resting potential. The corresponding values for Na+ and 01-were 1 and 1-2 ,arrho cm-2 respectively.