Movement of Substances Across a Plasma Membrane and its Application in Daily Life

Movement of Substances Across a Plasma Membrane and Its Application in Daily Life

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Movement of Substances Across a Plasma Membrane and Its Application in Daily Life

	Phenomena of plant wilting:

	Excessive use of fertilisers may cause wilting in plants. Dissolved fertilisers will cause soil water to be hypertonic to the sap cell of roots. Consequently, water will diffuse by osmosis from the roots’ cell sap to the soil, and cells will become plasmolysed. Cells in plants will recover once they are watered. However, if the period of plasmolysis is prolonged, wilted plants will eventually die.

Application in daily life:

Rehydration drinks such as oral rehydration salts help to recover loss of water and electrolytes in individuals with diarrhea.
Isotonic drinks help athletes to recover loss of water and electrolytes such as potassium and sodium through perspiration.
Saline solutions, normally used in medicine, are isotonic solution to the blood plasma. It contains 0.85–0.90 g sodium chloride per 100 ml.
Liposomes are vesicles that contain aqueous solution surrounded by a phospholipid bilayer membrane. Liposomes are used to protect drugs or active substances taken orally from being destroyed by gastric juices. This way, drugs can reach the target cells.
Reverse osmosis is a technology commonly used to extract fresh water from seawater using the desalination process. In reverse osmosis equipment, pressure is applied to push the seawater through a semi-permeable membrane. The membrane allows water molecules to pass through it but not foreign particles, salt, and microorganisms. As a result, only pure fresh water is released.