What term refers to the movement of water molecules across a semipermeable membrane?

The correct term for the movement of water molecules across a semipermeable membrane is osmosis. This process specifically involves the passive transport of water, where it moves from an area of lower solute concentration to an area of higher solute concentration. The semipermeable membrane allows water molecules to pass through while restricting the flow of solute particles, thereby creating a balance in the concentration of solutes on either side of the membrane. By understanding osmosis, one can appreciate how cells maintain their turgor pressure and how substances are transported within biological systems.

Filtration refers to the movement of solutes and solvent through a membrane due to a pressure gradient, not specifically water movement. Transport is a general term that can refer to various methods of moving substances across membranes, including active and passive processes, but it does not specify the nature of the movement. Diffusion, while it involves the spread of molecules from an area of higher concentration to an area of lower concentration, applies to solutes and gases rather than being specific to water movement across semipermeable barriers.