Figure 7.

The FV current poorly discriminates between Na⁺ and K⁺. I/V relations in a high-conductance stable state, 100 mm KCl in the bath, and either 100 mm KCl or 500 mm NaCl in the pipette (the arrow indicates the reversal potential of the whole-vacuole current for the latter case). A and B, Young (A) and old (B) quinoa leaves. Values are means ± se (n = 5–6 mesophyll vacuoles). C, Plot of conductance versus voltage. Symbols are as in A and B. Measurements were taken 30 min after vacuole perfusion, when currents reached their maximum values.