Intracellular osmolarity

Value 85 osmol/m^3
Organism Chlamydomonas spp.
Reference Raven JA, Doblin MA. Active water transport in unicellular algae: where, why, and how. J Exp Bot. 2014 Dec65(22):6279-92. doi: 10.1093/jxb/eru360. p.6284 right column 2nd paragraphPubMed ID25205578
Primary Source John A Raven. The energetics of freshwater algae energy requirements for biosynthesis and volume regulation, New Phytologist, Volume 92, Issue 1 September 1982 Pages 1–20 DOI: 10.1111/j.1469-8137.1982.tb03358.x
Comments P.6284 right column 2nd paragraph: "While this may seem a rather small value for the external recycling of ions assuming an external osmolarity of 2 osmol/m^3 (primary source), the osmolarity of the growth medium (Polley and Doctor, 1985) used by Malhotra and Glass (1995) is, assuming an osmotic coefficient of 0.9 for ions, 72 osmol/m^3, which is slightly lower than the 85 osmol/m^3 for the intracellular osmolarity of Chlamydomonas cited by Raven (primary source). This suggests that no contractile vacuole activity occurs in the work of Malhotra and Glass (1995). More focused experiments are needed to determine if potassium (and chloride) external recycling can account for contractile vacuole activity." Primary source p.8 3rd paragraph: "[Investigators] assume an internal osmolarity for a Chlamydomonas-type flagellate of 85 Osmol/m^3 (i.e. a typical rather than a minimal value: see Raven, 1974, 1976, 1980)."
Entered by Uri M
ID 112732