Fig. 3B: Passive Diffusion, Step 2

Passive diffusion is the net movement of gases or small uncharge polar molecules across a phospholipid bilayer membrane from an area of higher concentration to an area of lower concentration . Examples of gases that cross membranes by passive diffusion include N2, O2, and CO2; examples of small polar molecules include ethanol, H2O, and urea.

Illustration of Passive Diffusion, Step 2.jpg by Gary E. Kaiser, Ph.D.
Professor of Microbiology, The Community College of Baltimore County, Catonsville Campus
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Last updated: Feb., 2018
Please send comments and inquiries to Dr. Gary Kaiser