Question

which process does osmosis involve?
movement of water across a cell membrane
movement of water up a concentration gradient
movement of solute up a concentration gradient
movement of solute across the cell membrane

Explanation:

Osmosis is defined as the movement of water molecules across a selectively permeable membrane (like a cell membrane) from an area of lower solute concentration (higher water concentration) to an area of higher solute concentration (lower water concentration), i.e., down a concentration gradient. The key is the movement of water across a cell membrane. The second option is incorrect as water moves down, not up, the concentration gradient. The third and fourth options are incorrect as osmosis involves water (solvent) movement, not solute movement.

Answer:

A. movement of water across a cell membrane