## Osmosis

Debate and discussion of any biological questions not pertaining to a particular topic.

Moderator: BioTeam

### Osmosis

Im really sorry to be using this site for coursework, but what makes a difference on osmosis, apart from temperature. PLEASE help Me.
JIM
parryarmy15
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Osmosis is opposed by increasing the pressure in the region of high solute concentration with respect to that in the low solute concentration region. The force per unit area, or pressure, required to prevent the passage of water through a selectively-permeable membrane and into a solution of greater concentration is equivalent to the osmotic pressure of the solution, or turgor. Osmotic pressure is a colligative property, meaning that the property depends on the concentration of the solute but not on its identity.

Increasing the pressure increases the chemical potential of the system in proportion to the molar volume (δμ = δPV). Therefore, osmosis stops, when the increase in potential due to pressure equals the potential decrease from Equation 1, i.e.:

Where δP is the osmotic pressure and V is the molar volume of the solvent.

For the case of very low solute concentrations, -ln(1-x2) ≈ x2 and Equation 2 can be rearranged into the following expression for osmotic pressure:

Keith

keef
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### surface area

could you help me with my prediction on water potential of a potato tuber cell when placed in sugar solutions of different concentrations?
xXxBiOlOgY_BaBexXx
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### osmosis

Please can someone suggest a reason as to why when sugar is sprinkled over fruit - eg strawberries - liquid is later found to collect in the dish?

I am assuming that it is due to water in the fruit (higher concentration) diffusing through to the sugar via osmosis to a region of lower concentration and therefore the excess is found at the bottom of dish - is that right? Much appreciated for any help given thanks!
welshwoman
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