| Popis: |
Stomatal apertures and concentrations of potassium, malate and sugars within the epidermis were measured during stomatal opening and closure; the location of K+ was also estimated by cobaltinitrite staining. The concentration of K+ in the epidermis as a whole did not change during stomatal opening and closure, but K+ migrated between epidermal and guard cells. Concentrations of sugars also remained constant. By contrast, there was a positive relationship between concentration of malate and aperture. These and other results emphasize an appreciable degree of isolation of the epidermis. |
