Friday, December 6, 2013

Osmosis and H2O balance of Cells



Osmosis is the diffusion of water across a selectively permeable membrane. Water diffuses across a membrane from the region of lower solute concentration to the region of higher solute concentration until the solute concentration is equal on both sides.


H2O balance of Cells


Tonicity is the ability of a surrounding solution to cause a cell to gain or lose water.
Isotonic solution: Solute concentration is the same as that inside the cell; no net water movement across the plasma membrane.
Hypertonic solution: Solute concentration is greater than that inside the cell; cell loses water.
Hypotonic solution: Solute concentration is less than that inside the cell; cell gains water.
Hypertonic or hypotonic environments create osmotic problems for organisms.