AP BIOLOGY

Detailed explanation-1: -Osmosis is a special type of diffusion, namely the diffusion of water across a semipermeable membrane. Water readily crosses a membrane down its potential gradient from high to low potential (Fig. 19.3) [4]. Osmotic pressure is the force required to prevent water movement across the semipermeable membrane.

Detailed explanation-2: -Osmosis is a type of simple diffusion in which water molecules diffuse through a selectively permeable membrane from areas of high water concentration to areas of lower water concentration.

Detailed explanation-3: -Osmosis is the diffusion of water from high concentration to low concentration. When you drink water, your cells have a lower concentration of water than the water in your digestive system. So water flows across the cell membrane (from high concentration to low concentration) of your cells hydrating you.

Detailed explanation-4: -Diffusion is the movement of particles from an area of higher concentration to lower concentration to equalize concentration while osmosis is the movement of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution.

Detailed explanation-5: -The simplest mechanism by which molecules can cross the plasma membrane is passive diffusion. During passive diffusion, a molecule simply dissolves in the phospholipid bilayer, diffuses across it, and then dissolves in the aqueous solution at the other side of the membrane.