2 Concentration Gradient Concentration – the amount of solute compared to water in the solutionHigh Concentration = large amount of solute in the solutionLow Concentration = small amount of water in the solutionConcentration Gradient– the difference in the amount of solute between different parts of the solution (sometimes across two sides of a membrane).
3 Cell membrane transport There are 2 types of cell membrane transport:Passive TransportThings flow fromHigh to low concentrationDOES NOT USE ATP (energy)Active TransportLow to high concentrationUSE ATP (energy)
4 Another perspective on passive and active transport
5 THE GOAL IS…..Equilibrium!!! When is equilibrium reached when discussing cell membrane transport?When the concentrations of particles are the same on both sides
6 Passive Transport Diffusion The movement of particles from areas of high concentration to low concentration
7 Facilitated Diffusion Particles flow from high concentration to low concentration but this time they need the help of proteins to get through the cell membrane.
9 Passive transport Osmosis The facilitated diffusion of water across a selectively permeable membraneImportant in maintaining cell homeostasisWater moves from high concentration to low concentration
10 OsmosisOsmosis is controlled by the amount of solutes on either side of a membrane
11 Review of Solution Terms Solution = Saltwater Solvent = Water Solute = Salt
12 Osmosis – Types of Solutions When dealing with osmosis, water can either move into the cell or out of it.The solute cannot move to equal out the solution so the water has to.We describe the solutions that cells are in as either hypotonic, isotonic, or hypertonic.90 %soluteWhat are the concentrations?40% solute
13 Isotonic SolutionIsotonic solution – Concentration of solute is the same in the cell and the area around the cell.Give me an example of an isotonic solution that some of you use everyday
15 Hypertonic SolutionHypertonic solution – concentration of solute is higher in the solution than in the cell.Where is water going to move in order to reach equilibrium (Equal concentrations)?Outside the cell
16 Hypertonic solutionsSince water moves out of the cell the cell will shrinkSo, Hypertonic solution, high concentration of solute, cell will shrink
17 Plant and animals cells in a Hypertonic Solution
18 Hypotonic SolutionHypotonic Solution – Concentration of solute is lower in the solution than in the cell.Where is water going to move in order to reach equilibrium (Equal concentrations)?Inside the cell
19 Hypotonic solutionsSince water moves into the cell the cell can explodeSo, Hypotonic solution, low concentration of solute, cell can explode