|MadSci Network: Cell Biology|
The osmotic potential of the cell sap in onion epidermal cells (or any plant cell, for that matter) can vary greatly depending upon how the cells have been treated - e.g. depending on exposure to drying, temperature, etc. Between 630 to 470 mosm seems to be the range of values I've found in a quick seach of the lierature. See: PALTA, J. P., LEVITT, J., STADELMANN, E. J. & BURKE, M. J. (1977) Dehydration of Onion Cells: A Comparison of Freezing vs. Desiccation and Living vs. Dead Cells. Physiologia Plantarum 41 (4), 273-279. PALTA, J. P , LEVITT, J., & STADELMANN, E.J. (1977) Freezing Injury in Onion Bulb Cells I. Evaluation of the conductivity method and analysis of ion and sugar efflux from injured cells. Plant Physiol. (1977) 60, 393-397
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