What are the differences between the three types of passive transport.
If a cell’s contents have a lower solute concentration than the solution that surrounds it, what will happen to the cell?
The three types of passive transport are diffusion, osmosis, and facilitated diffusion.
1. Diffusion: Diffusion is the movement of molecules from an area of high concentration to an area of low concentration. It occurs across a concentration gradient and does not require the use of energy.
2. Osmosis: Osmosis specifically refers to the movement of water molecules across a selectively permeable membrane. It occurs from an area of low solute concentration (hypotonic solution) to an area of high solute concentration (hypertonic solution), to reach an equilibrium. Similarly to diffusion, osmosis does not require energy.
3. Facilitated diffusion: Facilitated diffusion involves the movement of molecules across a membrane with the help of transport proteins. These proteins create channels or carriers that allow specific molecules to pass through the membrane. Like diffusion and osmosis, facilitated diffusion does not require energy.
If a cell's contents have a lower solute concentration than the solution that surrounds it (hypotonic solution), water molecules will tend to move into the cell by osmosis. This is because water moves from an area of low solute concentration (outside the cell) to an area of higher solute concentration (inside the cell). As a result, the cell may swell or burst (in extreme cases) due to the increase in water intake.