DIFFUSION AND OSMOSIS (Passive Transport (two types (diffusion (molecules…
DIFFUSION AND OSMOSIS
does not require energy input from a cell
molecules diffuse down a concentration gradient without energy
(they go from high to low concentration)
Some molecules can't easily diffuse across a cell membrane.
Facilitated diffusion is diffusion with the help of transport proteins.
the diffusion of water molecules across a semipermeable membrane
three types of solutions in osmosis
The solution has the same concentration as the cell.
The cell stays the same
The solution has a higher concentration of solutes than the cell. The cell has more water
Water moves out of the cell and the cell will shrink.
The solution has less concentration than the cell. The cell has less water.
Water will move into the cell causing the cell to swell.
(Key Concept) Materials move across membranes because of concentration differences.
The difference in the concentration of a substance from one location to another is called a