Simple diffusion

From WikiMD's Food, Medicine & Wellness Encyclopedia

Simple Diffusion is a type of passive transport in biology that does not require the assistance of transport proteins. It is the random movement of molecules from an area of high concentration to an area of low concentration, resulting in the even distribution of molecules. This process continues until equilibrium is reached.

Overview[edit | edit source]

Simple diffusion is a fundamental process in cell biology. It is the primary mechanism by which small, nonpolar molecules such as oxygen and carbon dioxide move across cell membranes. This process is driven by the concentration gradient, which is the difference in concentration of a substance across a space or a membrane.

Mechanism[edit | edit source]

In simple diffusion, molecules move from an area of higher concentration to an area of lower concentration until equilibrium is reached. This movement is due to the inherent kinetic energy of molecules, which causes them to move randomly. The rate of diffusion is influenced by factors such as temperature, pressure, concentration gradient, and the size and polarity of the molecules.

Factors Affecting Simple Diffusion[edit | edit source]

Several factors can affect the rate of simple diffusion:

  • Temperature: Higher temperatures increase the kinetic energy of the molecules, thus increasing the rate of diffusion.
  • Pressure: An increase in pressure can increase the rate of diffusion by decreasing the distance the molecules must travel.
  • Concentration gradient: The greater the difference in concentration, the faster the rate of diffusion.
  • Molecular size and polarity: Smaller, nonpolar molecules diffuse more rapidly than larger, polar molecules.

Role in Biological Systems[edit | edit source]

Simple diffusion plays a crucial role in biological systems. It is responsible for the exchange of oxygen and carbon dioxide between cells and their environment, the delivery of nutrients to cells, and the removal of waste products from cells.

See Also[edit | edit source]

Simple diffusion Resources
Doctor showing form.jpg
Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.


Contributors: Prab R. Tumpati, MD