ISSN:
1432-1793
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Sodium and chloride concentrations of the haemolymph were determined in Sphaeroma rugicauda Leach and S. serratum Fabricius acclimatized to a range of salinities. Sodium loss and uptake (using 22Na) were measured in salinities below 1.1‰ for S. rugicauda and 7.2‰ for S. serratum. Potential differences between haemolymph and medium indicate active uptake of both ions in certain salinities. The active-uptake component of total sodium-influx was found to be related non-linearly to the sodium concentration of the medium. Curves of $$\dot 6$$ were fitted to the activeuptake data. Km values indicate that, in S. rugicauda, the sodium uptake system has a greater affinity for sodium than in S. serratum. These findings are discussed in relation to the distribution of each species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00347426
