Final answer:
Osmosis is the transport of water molecules through a semi-permeable membrane from a region of higher water concentration to a region of lower concentration, driven by the desire to equalize concentrations on both sides of the membrane.
Step-by-step explanation:
The NET movement of water molecules described in the question is known as osmosis.
Osmosis is a fundamental biological process where water moves through a semi-permeable membrane from a region with a higher concentration of water (less solute) to a region with a lower concentration of water (more solute).
This allows cells to maintain fluid balance and is critical for numerous physiological processes. In osmosis, the goal is to equalize concentrations by the movement of water rather than solutes, because the semi-permeable membrane blocks the solute particles from passing through.
This is illustrated when a beaker is divided by a semi-permeable membrane: water moves to the hypertonic side (where there is a higher solute concentration and lower water concentration) until equilibrium is reached.