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||P.919 middle column top paragraph: "Also, using 80 mM as the cytoplasmic K+ concentration (primary sources) in the Nernst equation, it follows that a Vm [resting membrane potential] of at least -230 mV is required for K+ uptake to occur passively through a channel." Primary sources  &  investigated Arabidopsis thaliana roots & barley (Hordeum vulgare L.) root cells, respectively.