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Osmosis

Key Stage 4

Meaning

Osmosis is the diffusion of water from a high water concentration to a low water concentration through a partially permeable membrane.

About Osmosis

Osmosis is how plants get water through their roots and how animals gain water through the walls of the Small Intestine and Large Intestine.
Osmosis is how cells absorb and release water.
Osmosis is a passive process which means it does not require energy to take place.
A high water concentration means water with very little dissolved salts or sugars. A low water concentration is water with a high concentration of salts or sugars in solution.
A partially permeable membrane is a membrane which only allows through certain molecules. This is often small molecules like water that can pass through but not larger molecules like sugar. However, the cell membrane is selectively permeable which means it can control which molecules pass through.

NB: Water Concentration may be referred to as 'Water Potential' in some textbooks.

References

AQA

Osmosis, page 18, GCSE Combined Science; The Revision Guide, CGP, AQA
Osmosis, page 21, GCSE Biology; The Revision Guide, CGP, AQA
Osmosis, pages 16-19, GCSE Biology; Third Edition, Oxford University Press, AQA
Osmosis, pages 33-5, GCSE Biology, Hodder, AQA
Osmosis, pages 33-5, GCSE Combined Science Trilogy 1, Hodder, AQA
Osmosis, pages 48, 49, GCSE Combined Science Trilogy; Biology, CGP, AQA
Osmosis, pages 54, 55, GCSE Biology, CGP, AQA
Osmosis, pages 88-91, 92, 108-9, 198, GCSE Biology; Student Book, Collins, AQA
Osmosis; investigating, pages 49, 50, GCSE Combined Science Trilogy; Biology, CGP, AQA
Osmosis; investigating, pages 55, 56, GCSE Biology, CGP, AQA
Osmosis; investigation of, page 41, GCSE Combined Science Trilogy 1, Hodder, AQA

Edexcel

Osmosis, page 21, GCSE Biology; The Revision Guide, CGP, Edexcel
Osmosis, pages 18, 19, GCSE Combined Science; The Revision Guide, CGP, Edexcel
Osmosis, pages 24-25, GCSE Biology, Pearson, Edexcel
Osmosis, pages 49, 50, GCSE Biology, CGP, Edexcel
Osmosis; investigating, page 22, GCSE Biology; The Revision Guide, CGP, Edexcel
Osmosis; investigating, pages 52-54, GCSE Biology, CGP, Edexcel

OCR

Osmosis, page 26, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR
Osmosis, pages 31-33, Gateway GCSE Biology; The Revision Guide, CGP, OCR
Osmosis, pages 60-61, 80, 124-125, 264-265, Gateway GCSE Biology, Oxford, OCR
Osmosis; experiments, page 32, Gateway GCSE Biology; The Revision Guide, CGP, OCR