cell transport 1/21/25

fluid mosaic model

current model of the plasma membrane which is able to bend and selectively permeable

selectively permeable

only certain things are able to pass through

able to pass through

small and nonpolar molecules

unable to pass through

large and polar molecules

passive transport

movement of a substance with no energy

diffusion

moment of a substance down their concentration gradient

osmosis

the diffusion of water

tonicity

amount of solute in a solution

hypertonic solution

more solute

hypotonic

less solute

isotonic

equal amount of solute

animal cell in hypertonic solution

cell shrivels (water moves out of cell)

animal cell in hypotonic solution

cell lyses/bursts (water moves into the cell)

animal cell in isotonic solution

normal (water stays)

plant cell in hypertonic solution

plasmolysis (cell membrane pulls away from the cell wall)

plant cell in hypotonic solution

turgid/normal (cell swells)

water potential

• used to determine the direction of water flow in plants

• osmosis + pressure