Osmosis Flashcards
What is osmosis?
The diffusion of water molecules across a partially permeable membrane from an area of high water potential to an area of low water potential
What is the water potential of pure water?
zero
What happens to the water potential of water when solutes are added?
Lowers
The more negative the water potential…
the stronger the concentration of solutes in the solution
What does isotonic mean?
Two solutions have the same water potential
Why is there no loss or gain of water in an isotonic solution?
There is no difference in water potential between the cell and the surrounding solution
What are solutions with a higher water potential compared to the inside of the cell called?
Hypotonic
What happens to the cell when in a hypotonic solution?
It swells as the water moves in
What are solutions with a lower water potential than the cell called?
Hypertonic
What happens to the cell when placed in a hypertonic solution?
It shrinks as water moves out
What three factors affect the rate of osmosis?
Water potential gradient
Thickness of exchange surface
Surface area of exchange surface
