Osmosis: movement of water from a region of high water potential to a region of low water potential through a partially permeable membrane. High water potential = lots of free water molecules, low solute concentration Low water potential = very few free water molecules, high solute concentration
Factors That Affect the Movement of Water in and out of Cells
* Solute concentration * If one solution has low solute concentration and the other has high solute concentration, then the movement of water will be faster. If they have similar solute concentrations then the movement of water will be slower. * Temperature * As you warm up the solution, the particles will move faster to lose or gain chemicals quicker. * Type of cell/tissue * Leaf cell may take up different amount of water compared to root cell. * Leaf cell – more solutes * Root cell – less solutes * Type of vegetable/plant * Cucumber – lots of water * Potato – very dry * Time of immersion * You must be on equilibrium set up. * Surface Area/Size of Sample * The larger the surface area, the quicker osmosis will happen. * Distance * The further the water molecules have to move, the slower the rate of osmosis. * Permeability of membrane * For water, the more permeable the membrane is, the faster the rate of osmosis. * For solutes, the more permeable the membrane is, the slower the rate of osmosis.
Hypothesis
Changing solute concentration has no effect on uptake of water I know this because...
Changing the solute concentration of a solution that plant tissue is immersed in will affect the movement of water in and out of that plant tissue I have made this hypothesis because... Osmosis is occurring – give definition, explain what it is
*Include a picture of osmosis*
Cannot use glucose because