6.4 Specialized Cells Flashcards
osmosis
the diffusion of water across a semi-permeable membrane
water diffuses from higher to
lower concentration
Water follows
Solute
when the solute dissolves in the
solvent, it makes a solution
hypertonic
higher in solute
when a cell is in a hypertonic solution
it will shrink
when a cell is in a hypotonic solution,
it will swell
hypotonic
lower in solute
isotonic
same solute concentration
no change in water
simple diffusion
particles move directly across the membrane
simple diffusion moves
small nonpolar molecules
facilitated diffusion
involves a carrier protein
facilitated diffusion moves
polar molecules
in diffusion, molecules move from
high to low concentration
active transport
cells move molecules against concentration gradient
active transport uses
a protein “pump”
active transport costs
energy/ATP
active transport goes from low to
high concentration
vescicles can help
move molecules in and out of the cell
endocytosis
move molecules in
exocytosis
move molecules out
can move large molecules or large
amounts of molecules
