Turgor pressure

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'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.

1 Mechanism
2 See also
3 External links
4 References

[edit] Mechanism

Plant cell under different environments

When a cell is in an environment of high water potential, water flows across the cell membrane into the cell, causing it to expand due to osmotic pressure. In plant cells, water enters the cell until the inside and outside water potential is equal, however, the cell wall prevents the cell from bursting, resulting in pressure on the cell wall from within.

The pressure of each cell wall against its neighbor results in stiffness that allows the plant to stay upright. Cells not adapted to hypotonic environments will burst due to the inflow of water if they have no strong membrane or cell wall.

The opposite condition in a plant cell, resulting from immersion in an environment of low water potential, is plasmolysis.

Turgor pressure is not only important in terms of plant rigidity, but also of key importance in microbial growth.

[edit] See also

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