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water potential

water potential Symbol Ψ. The difference between the chemical potential of the water in a biological system and the chemical potential of pure water at the same temperature and pressure. It is manifested as a force acting on water molecules in a solution separated from pure water by a membrane that is permeable to water molecules only and can be expressed as the sum of the solute potential and the pressure potential: Ψ = Ψs + Ψp

Water potential is measured in kilopascals (kPa). The water potential of pure water is zero; aqueous solutions of increasing concentration have increasingly negative values. Water tends to move from areas of high (less negative) water potential to areas of low (more negative) water potential. Osmosis in plants is now described in terms of water potential. In soils and other extracellular systems, another factor, called matric potential, can contribute significantly to water potential.

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"water potential." A Dictionary of Biology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

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"water potential." A Dictionary of Biology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-3

water potential

water potential
1. (osmotic potential, chemical potential) The difference between the energy of water in the system being considered and of pure, free water at the same temperature. The water potential of pure water is zero, so that of a solution will be negative. If there is a gradient of water potential between two plant cells, water will diffuse down the gradient until equilibrium is reached.

2. See CAPILLARY MOISTURE.

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"water potential." A Dictionary of Earth Sciences. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"water potential." A Dictionary of Earth Sciences. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential

"water potential." A Dictionary of Earth Sciences. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential

water potential

water potential
1. (chemical potential, osmotic potential) The difference between the energy of water in the system being considered and of pure, free water at the same temperature. The water potential of pure water is zero, so that of a solution will be negative. If there is a gradient of water potential between two plant cells, water will diffuse down the gradient until equilibrium is reached.

2. See capillary moisture.

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"water potential." A Dictionary of Ecology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"water potential." A Dictionary of Ecology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-0

"water potential." A Dictionary of Ecology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-0

water potential

water potential The difference between the energy of water in the system being considered and of pure, free water at the same temperature. The water potential of pure water is zero, so that of a solution will be negative. If there is a gradient of water potential between two cells, water will diffuse down the gradient until equilibrium is reached.

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"water potential." A Dictionary of Zoology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"water potential." A Dictionary of Zoology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-2

"water potential." A Dictionary of Zoology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-2

water potential

water potential
1. A measure of the energy that causes water to enter plant cells. There is a net movement of water from a region of high water potential to one of low water potential.

2. Surface tension. See CAPILLARY MOISTURE.

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"water potential." A Dictionary of Plant Sciences. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"water potential." A Dictionary of Plant Sciences. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-1

"water potential." A Dictionary of Plant Sciences. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/water-potential-1