Turgor pressure

Turgor pressure

'Turgor pressure' or turgidity is the main pressure of the cell contents against the cell wall in plant cells and bacteria cells, determined by the water content of the vacuole, resulting from osmotic pressure, i.e. the hydrostatic pressure produced by a solution in a space divided by a semipermeable membrane due to a differential in the concentration of solute. Turgid plant cells contain more water than flaccid cells and exert a greater osmotic pressure on its cell walls.

Turgor is a force exerted outward on a plant cell wall by the H2O contained in the cell. This force gives the plant rigidity, and may help to keep it erect. Turgor may also result in the bursting of a cell.

Wilting

" [P] lants wilt not only when they lose water through evaporation but also when they are surrounded by an aqueous solution of common salt, potassium chloride, magnesium chloride, sugar or other substance, if the solution is of higher osmotic pressure, whereas they do not wilt if the osmotic pressure is lower." [ [http://nobelprize.org/nobel_prizes/chemistry/laureates/1901/hoff-lecture.pdf Plants wither due to salts (pdf)] ]

ee also

*Cell wall
*Osmotic pressure
*Osmosis

References

Campbell, N. A., Reece, J. B. Biology: Sixth Edition; Benjamin Cummings: New York, NY, 2002; Vol. 1.

External links

* [http://www.biologie.uni-hamburg.de/b-online/e22/22c.htm Osmotic pressure]
* [http://www.microscopy-uk.org.uk/mag/artoct99/plantupright.html How do non woody plants stay upright?]
* [http://lsvr12.kanti-frauenfeld.ch/KOJ/Java/Osmosis.html NetLogo Turgor simulation for educational use (Java Applet for fast PCs)]
* [http://lsvr12.kanti-frauenfeld.ch/KOJ/Java/Osmosis_fast.html NetLogo Turgor simulation for educational use (Java Applet, runs fast also on slow PCs)]


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Look at other dictionaries:

  • turgor pressure — noun : the actual pressure developed by the fluid in a turgid plant cell as a result of endosmosis as contrasted with the potential maximum pressure that fluid of the same concentration could theoretically develop …   Useful english dictionary

  • turgor pressure — The pressure within a cell resulting from the absorption of water into the vacuole and the imbibition of water by the protoplasm …   Glossary of Biotechnology

  • Pressure Flow Hypothesis — The Pressure Flow Hypothesis, also known as the Mass Flow Hypothesis, is the best supported theory to explain the movement of food through the phloem.[1] It was proposed by Ernst Münch, a German plant physiologist in 1930.[2] A high concentration …   Wikipedia

  • turgor movement — noun : a reversible change in position of a plant part due to a change in turgor pressure of various cells (as in sleep movements) compare nyctitropism …   Useful english dictionary

  • turgor — [tʉr′gər, tʉr′gôr΄] n. [LL < L turgere, to swell] 1. turgescence; turgidity 2. the normal distention or rigidity of living animal and plant cells due to pressure against the plasma membrane from within by the cell contents …   English World dictionary

  • turgor — /terr geuhr/, n. 1. Plant Physiol. the normal distention or rigidity of plant cells, resulting from the pressure exerted by the cell contents on the cell walls. 2. the state of being swollen or distended. [1875 80; < LL, equiv. to L turg(ere) to… …   Universalium

  • turgor — The pressure within cells, especially plant cells, derived from osmotic pressure differences between the inside and outside of the cell giving rise to mechanical rigidity of the cells. Turgor drives cell expansion and certain movements such as… …   Dictionary of molecular biology

  • turgor — n. normal pressure or rigidity of plant cells owing to the pressure exerted by the fluid inside the cells (Plant Physiology); swelling, distention …   English contemporary dictionary

  • turgor — noun a) the pressure produced by a solution in a space that is enclosed by a differentially permeable membrane. b) the state of being turgid …   Wiktionary

  • turgor — Fullness. [L., fr. turgeo, to swell] t. vitalis the normal fullness of the capillaries. * * * tur·gor tər gər, .gȯ(ə)r n the normal state of turgidity and tension in living cells esp the rigidity of a plant that is due to the pressure of the… …   Medical dictionary

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