What is the movement of water molecules from an area of high concentration to an area of low concentration through a selectively permeable membrane called?

The movement of water molecules from an area of high concentration to an area of low concentration through a selectively permeable membrane is specifically defined as osmosis. This process is crucial for maintaining cellular homeostasis and is a type of passive transport that does not require energy input from the cell.

In osmosis, water molecules move in response to the concentration gradient, seeking to equalize the concentration on both sides of the membrane. Selectively permeable membranes allow certain molecules, like water, to pass through while restricting others, which is essential for controlling the internal environment of cells.

To differentiate this from other processes: diffusion involves the movement of solutes from high to low concentration, which does not specifically pertain to water movement. Active transport, on the other hand, requires energy to move substances against their concentration gradient, and filtration is a process where physical pressure helps separate substances based on size, such as in kidneys, which does not involve selective concentration gradients in the same manner as osmosis.