title: THE EXPERIMENTAL PRODUCTION OF DOUBLE PEAKS IN CHARA ACTION CURVES AND THEIR RELATION TO THE MOVEMENT OF POTASSIUM.
abstract: The action curve in Chara seems to depend (as in Nitella) on the outward movement of K(+) from the sap. Presumably the increase in permeability in the inner protoplasmic surface and the outward movement of K(+) destroy the concentration gradient of K(+) across the inner protoplasmic surface. Hence the outwardly directed P.D. disappears, causing the rise (spike) of the action curve. The outer protoplasmic surface is normally insensitive to K(+). But when it is made sensitive to K(+) by treatment with guanidine the outwardly moving K(+) sets up a positive P.D. on reaching the outer surface and this causes the action curve to fall, producing a peak. Then the curve has 2 peaks, the second being due to the process of recovery. The action curve thus comes to resemble that of Nitella in which the outer protoplasmic surface is normally sensitive to K(+).
authors.affiliation: Laboratories of The Rockefeller Institute for Medical Research.
authors.forename: W J
authors.initials: WJ
authors.lastname: Osterhout
authors.forename: S E
authors.initials: SE
authors.lastname: Hill