Author: Nathan Lampson
This lesson explains the process of osmosis. It explains how osmosis is a passive form of transport, used to move water molecules across a semi-permeable membrane, down their concentration gradient.
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the movement of water molecules through  a semi-permeable membrane.

Osmosis is considered a mode of passive transport because it does not require any energy.


Concentration Gradient

fewer molecules on one side of a membrane than on the other side of a membrane



When there is a higher concentration of water molecules on one side of a membrane.

More water molecules move from the side with a high concentration to the area with a low concentration of water.

Source: Concepts in Biology Twelfth Edition Eldon Enger, et al.