3.2 osmosis Flashcards
define osmosis
the diffusion of water molecules from one region of higher water potential (dilute solution) to a region of lower water potential (concentrated solution), through a partially permeable membrane
what are some examples of partially permeable membranes?
cell membrane; visking tubing
what is a dilute solution called?
high water potential
what is a concentrated solution?
low water potential
define water potential
a measure of the tendency for water to move out of a solution; the more water in the solution, the greater its water potential
what is meant by partially permeable membranes?
membranes that allow some substances pass through them, but not others
in what condition don’t plant cells burst?
plant cells don’t burst in pure water
what are animal cells surrounded by?
tissue fluids
what do cell membranes separate?
cytoplasm and the solution surrounding the cell
what is cytoplasm made up of?
protein and other substances in water
in what condition will osmosis occur?
if solutions are of different concentration
what happens when too much water molecules diffuse from the dilute solution outside the cell into the concentrated solution in the cell?
the cell swells and eventually bursts
what happens when too much water molecules diffuse out of the concentrated solution outside the cell from the dilute solution in the cell?
the cytoplasm shrinks and the cell shrivels up
how does a cell wall stops a plant cell from bursting?
as the cytoplasm presses out against the cell wall, but the wall resists and presses back on the contents
what condition are plant cells usually in?
they’re usually turgid
