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The Role of Diffusion in Living Organisms
a) In Plants
Diffusion plays an important role in plants in that:
It helps in absorption of mineral salts from the soil to the plant. Most salts dissolve in soil water. For those salts whose concentration in soil water is higher that their concentration in the cell sap of root hair cells, they move into the root hair cells through diffusion. Plants require mineral salts for numerous life processes.
Diffusion plays a role in gaseous exchange in plants. The respiratory gases (oxygen and carbon (IV) oxide) diffuse across the stomata and lenticels of plants.
Diffusion also contributes to the transportation of manufactured food materials from the leaves to other parts of the plant.
b) In Animals
In animals diffusion plays the following important roles
It helps in the absorption of digested food materials in the alimentary canal. End products of digestion such as amino acids and glucose diffuse across the wall of the ileum into the blood for transport to other parts of the animal body.
Diffusion also plays a significant role in gaseous exchange in animals. In animals, gaseous exchange occurs at certain structures known as respiratory surfaces.
These include the skin, gills, lungs, tracheal system and the cell membrane (in unicellular organisms). Gaseous exchange at these surfaces occurs through the process of diffusion.
Diffusion is important in excretion of nitrogenous wastes especially in unicellular animals.
Githiari answered the question on October 13, 2017 at 20:06
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