What is the net movement of water through a semipermeable membrane called?

The net movement of water through a semipermeable membrane is called osmosis. This process occurs when water molecules move from an area of lower solute concentration (where there is a higher concentration of water) to an area of higher solute concentration (where there is a lower concentration of water) in order to achieve equilibrium on both sides of the membrane. The semipermeable membrane allows water to pass through while restricting the movement of solute particles, facilitating this crucial biological process.

Osmosis is essential for many physiological functions in organisms, such as maintaining cell turgor in plants, regulating fluids in animal cells, and balancing electrolytes in the bloodstream. It is a passive process that does not require energy expenditure because it relies on the natural movement of water molecules driven by concentration gradients. Understanding osmosis is fundamental in fields such as biology and medical sciences, where fluid balance is critical.