Difference Between Osmosis and Imbibition

Main Difference

The main difference between osmosis and imbibition is that osmosis refers to the spontaneous movement of water molecules from a region of higher water potential to the region of low water potential through semi-permeable membrane whereas, imbibition refers as the process of absorbing water by a solid substance without forming a solution.

Osmosis vs. Imbibition

Osmosis is the process of spontaneous movement of water molecules from a region of high water potential to the region of low water potential through a semi-permeable membrane whereas, imbibition refers as the process of absorbing water by a dissolving substance. Osmosis does not include a solid substance, whereas imbibition includes a solid substance. Osmosis comprises a semi-permeable membrane whereas, imbibition does not comprise of a semi-permeable membrane. Osmosis needs solute particles, whereas; imbibition needs colloidal particles. Osmosis does not produce heat during the process whereas, imbibition produces heat during the process. Osmosis is the process where low pressure can be developed whereas, in imbibition, high pressure develops during the process. Osmosis has two types; exosmosis and endosmosis whereas, imbibition has no further types. Osmosis consists of two solutions as pure water and an aqueous solution whereas, imbibition does not consist of any two types of solutions. Osmosis requires the presence of osmotically active solutes whereas, imbibition needs the colloidal and hydrophilic substances. Osmosis does not cause an increase in volume whereas, imbibition causes an increase in volume. Osmosis takes place only in gases, liquids, and solids whereas imbibition takes place in the living and dead cells both. Osmosis is not a reversible process whereas imbibition is the reversible process.

Comparison Chart

OsmosisImbibition
Osmosis refers to the spontaneous movement of water molecules from a region of higher water potential to the region of low water through a semi-permeable membraneImbibition refers to the process of absorbing water by a solid substance without forming a solution.
Involvement of a Solid Substance
Osmosis does not include a solid substanceImbibition includes a solid substance
Involvement of a Semi-permeable Membrane
Osmosis comprises a semi-permeableImbibition does not include semi-permeable
The requirement of Colloidal Particles
Osmosis needs solute particlesImbibition needs colloidal particles
Heat Generation
Osmosis does not produce heatImbibition produces heat
Pressure Development
During osmosis does not produce a high pressureImbibition process high pressure during the process
Types
It has two types; exosmosis and endosmosisIt has no further types
Occurrence
It takes place in gases, liquids, and gasesIt takes place in dead and living cells
Reversible Process
Osmosis is an irreversible processImbibition is a reversible process
Solution
Osmosis generally operates in a solution that is separated by a semi-permeable membraneusually does not Imbibition produce a solution

What is Osmosis?

Osmosis is a process of spontaneous movement of water from a region of high water potential to a region of low water potential. It does not need solid particles. It also requires a semi-permeable membrane. Osmosis requires solute particles, not the colloidal particles. Osmosis does not produce heat during the process. It takes place only in gases; liquids and, solids. Osmosis is an irreversible process. Osmosis generally operates in a solution that is separated by a semi-permeable membrane. Osmosis usually produces a low-pressure potential called as osmotic potential. Osmosis consists of two solutions as pure water and aqueous solution. Osmosis is also a type of diffusion. Osmosis is a type of passive process in which no energy is required. Osmosis is a physical process in which any solvent can pass through the selectively permeable membrane separating two solutions of different concentration. Osmosis can be used to do work. Osmosis is an important process in biological systems as the cell membranes are the selectively permeable membrane.

Types

  • Endosmosis: When there is a low-water potential in the cell as compared to the cell outside, then water enters into the cell.
  • Exosmosis: When there is a high-water potential in the cell as compared to the cell outside, then leaves the cell.

Example

Osmosis is the process involves in the absorption of water from the soil for plants, osmosis in humans for water retention, etc.

What is Imbibition?

Imbibition refers to the process of absorbing water by a solid substance without forming a solution. Imbibition needs solid particles. It does not require a semi-permeable membrane. Imbibition requires colloidal particles, not the solute particles. Imbibition produces heat during the process. It takes place in both the dead and living organisms. Imbibition is a reversible process. It does not consist of any solutions. It is a surface phenomenon. Imbibition causes an increase in the volume of the cell without taking any part in the cell solution. Imbibants are the solid particles which take part in the process, and the liquid that is imbibed is called as imbibate. The ability of imbibing is different in different imbibing.

Example

Germination of soaked seeds, the swelling of a wooden door during rains, etc.

Key Differences

  1. Osmosis is the process of spontaneous net movement of water molecules from a region of high water potential to the region of low-water potential through a semi-permeable membrane whereas imbibition refers as the process of absorbing water by a dissolving substance.
  2. Osmosis generally operates in a solution that is separated by a semi-permeable membrane, whereas in imbibition, it usually does not produce a solution.
  3. Osmosis does not include a solid substance, whereas the Imbibition consists of solid substance.
  4. Osmosis comprises a selectively permeable membrane conversely Imbibition does not include a selectively permeable membrane.
  5. Osmosis is an irreversible process; on the other hand, Imbibition is a reversible process.

Conclusion

The above discussion concludes that osmosis and imbibition are the two processes that simplify the water movements. The spontaneous movement of water molecules from a region of high water potential to a region of low water potential through a semi-permeable membrane called osmosis whereas adsorption of water molecules a solid particle is called imbibition.

Janet White

Janet White is a writer and blogger for Difference Wiki since 2015. She has a master's degree in science and medical journalism from Boston University. Apart from work, she enjoys exercising, reading, and spending time with her friends and family. Connect with her on Twitter @Janet__White

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