CBSE Class 12-science Answered
Molecules, like sugars, reach the carrier proteins in the membrane by diffusion and are then moved across the membrane from a region of high concentration to a region of low concentration. For example, if a cell is placed in a sugar solution the sugar molecules will diffuse and make contact with the carrier proteins located in the membrane.
Water moves across cell membranes by diffusion, in a process known as osmosis. Osmosis refers specifically to the movement of water across a semipermeable membrane, with the solvent (water, for example) moving from an area of low solute (dissolved material) concentration to an area of high solute concentration.