Osmosis (diffusion of water through a selectively permeable membrane)

Membrane X is permeable to water but not to protein

Which side has the highest concentration of protein?

Which side has the highest concentration of water?

Will this system ever reach equilibrium?

Osmosis

Equal concentrations of protein & water in Side A and Side B

Side A Side B Like other molecules, water follows the diffusion gradient.

Is protein concentration high or low in sides A/B?

When will this system reach equilibrium?

Isotonic Solutions

The movement of water into & out of living cells is vital to life processes. Ideally, cells are bathed in isotonic solutions

Concentration of solute molecules outside the cell is equal to the concentration of solute molecules inside the cell. There is no net change in water movement.

What would happen in an animal cell? Plant cell?

Hypotonic Solutions•Solutions in which the concentration of

solutes outside the cell is lower than that

found inside the cell.

•This means there is a higher concentration of water on the outside of the cell &

thus, water diffuses inward.

Cell swells/bursts•What would happen in an animal

cell? Plant cell?

Hypertonic Solutions•Solutions in which the concentration of solutes

outside the cell is greater than that found on the inside of the

cell.

•This means there is a lower concentration of

water on the outside, and thus, water diffuses

outward from the cell.

Cell shrinks•What would happen in an

animal cell? Plant cell?