Further Studies of Electro-Osmosis inNitellain Relation to Pores in Membranes

Abstract

By measuring the number of water molecules per ion which were moved electro-osmotically through cells of Nitella translucens and N. flexilis it has been shown that a significant difference existed between samples of these species in 1965. In each species the electro-osmotic efficiency was greater with Na⁺ than with K⁺⁺. Also 10^-4 to 10^-5 M IAA tended to decrease electro-osmotic efficiencies while IAA, after 30 min. treatment, produced a significant increase in water flow into the treated end of a living cell. Calculations based on this work suggest that about 10⁸–10⁹ pore sites per cm² exist on the surface membranes for Na⁺ or K⁺ ion transport.