Sinisa : Yes. Not in only single cells, either. Many plants have "antifreeze" sap, including northern Gymnosperms, and carry on growing, although slowly, well below zero C. 100% of the plants in permafrost areas are this type, and most temperate climate evergreens. Does this help? Steve (H.) -- Drop by and see me at : http://www.geocities.com/HotSprings/Spa/6811