Passive Transport (moving particles in with the concentration gradient)

Diffusion Movement of molecules from areas of high concentration to areas of lower concentration.

Concentration Gradient The difference in concentration of molecules across a space

Equilibrium When there is no concentration gradient.

Osmosis The movement of water across a membrane (Special type of diffusion)

3 Types of Solutions Hypotonic Solution - less Isotonic Solution - same Hypertonic Solution - more Hypotonic Solution Isotonic Solution Hypertonic Solution

LOW Hypotonic Solution HIGH LOW HIGH Solution that has less dissolved solutes than the cell. Instead Water flows from where it is most concentrated HIGH Salt would like to flow out of the cell but it cannot get out because of the cell membrane. Into the cell where there is more salt and less water LOW Less salt on outside of cell LOW More salt on the inside HIGH

Result of Hypertonic Solution on red blood cells

H2O H2O Isotonic Solution Solution that has an equal amount of solutes as the cell. H2O H2O

Hypotonic Isotonic Hypertonic

H2O Hypertonic Solution Solution that has more dissolved solutes than the cell. H2O

How Cells Deal With Osmosis Paramecium have a contractile vacuole to get rid of excess water.

Turgor Pressure The pressure that water exerts against a cell wall.

Plasmolysis When plant cell membranes pull away from the cell wall.

Facilitated Diffusion Molecules that cannot diffuse rapidly through the membrane use facilitated diffusion to get through the membrane with the help of a carrier protein.

Carrier Proteins Carrier Proteins- are found embedded in the membrane that change shape to allow larger molecules to cross.

Ion Channels Open and close to allow ions to flow down their concentration gradients.