What is the difference between osmotic potential and water potential

Matric potential is the component of water potential which is influenced by the presence of matrix. It has got a negative value in case of plant cell and tissue, the matric potential is often disregarded because it is not significant in osmosis. The equation for water potential may be simplified as follows:. Solute potential or osmotic potential : Solute potential is also known as osmotic potential. Osmotic potential or solute potential is the amount by which the water potential is reduced as a result of the presence of solute.

Solute potentials are always in negative values. A reference standard is pure water at a water potential equal to zero. A reduction from this value gives a negative number. Pressure potential : Pressure potential is a hydrostatic pressure. This is a pressure which develops in osmotic system due to osmotic entry or exit of water from it. A positive pressure develops in a plant cell or system due to entry of water into it. Positive hydrostatic pressure is also called turgor pressure.

Loss of water produces negative hydrostatic pressure. Plants are phenomenal hydraulic engineers. Using only the basic laws of physics and the simple manipulation of potential energy, plants can move water to the top of a meter-tall tree. Plants can also use hydraulics to generate enough force to split rocks and buckle sidewalks. Water potential is critical for moving water to leaves so that photosynthesis can take place.

Water potential is a measure of the potential energy in water, or the difference in potential energy between a given water sample and pure water at atmospheric pressure and ambient temperature.

The water potential in plant solutions is influenced by solute concentration, pressure, gravity, and factors called matrix effects. Water potential can be broken down into its individual components using the following equation:.

As the individual components change, they raise or lower the total water potential of a system. Solute molecules attract water molecules and restrict their freedom to move. Both water potential and osmotic potential are measured in Mpa. Water potential can be zero or a negative value, but it cannot be a positive value.

Moreover, pure water has zero water potential and zero osmotic potential. Overview and Key Difference 2. What is Water Potential 3. What is Osmotic Potential 4. Water potential is a measure of the concentration of free water molecules. Free water molecules are the water molecules that are free to move. Therefore, it is the potential energy in water. Pure water has zero water potential. Hence, water potential is the difference between the potential in a given water sample and pure water.

A given sample that contains solutes has a negative water potential. When there are lots of solute molecules, water molecules are less free to move; hence, there is negative potential energy.

When the concentration of the solutes in a sample is higher, the movements of water molecules are lesser in a solution. Water generally moves from high water potential to the low water potential.