ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Using the conventional methods of compartmental analysis has led us to recognize three main compartments in the Lemna cells: the cell-wall, cytoplasm and vacuolc. The half-times of Li+ isotopic exchange were of the order of a few minutes, a few hours and a few days, respectively. The possible existence of a 4th, small, and almost non-exchangeable compartment cannot be excluded. Despite different possible sources of uncertainty (ambiguity of the kinetic solutions, no uniformity of cell types in the plant material, uncertainties in the estimations of electric potentials), the data were consistent with i) Li+ being actively extruded from the cytoplasm, both towards the exterior and the vacuole, ii) the electrochemical potential difference of Li+ being of the order of -25 kj mol across the plasmalemma, and in the range of 5 to 10 kJ mol across the tonoplast, and iii) the passive permeability coefficients of Li+ being in the range of 10 to 10 m s both for the plasmalemma and the tonoplast.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1984.tb05919.x
