Diffusion vs osmosis

1. Diffusion Vs. Osmosis
Biology

2. Definitions
•Diffusion:
–Movement of molecules
from a place where there is
a large amount (high
concentration) to a place
where there is none or a
smaller amount (low
concentration).
•Osmosis:
–Diffusion of water across a
selectively permeable
membrane

3. Diffusion Diagram
•High Concentration
•Low Concentration
EquilibriumDiffusionBeginning

4. Osmosis Diagram
•Selectively Permeable
Membrane: Some
substances can pass
through and some cannot.

5. 3 Types of Solutions where OSMOSIS
can take place
•1. ISOTONIC – amounts of water
are equal inside and outside of
the cell (EQUILIBRIUM)
93%
93 % 93 %
93%
93%

6. 3 Types of Solutions where OSMOSIS
can take place
•2. HYPERTONIC – amount
of water inside the cell is
greater than outside of the
cell. (CELL SHRINKS)
85%
85% 85%
85%
93%

7. 3 Types of Solutions where OSMOSIS
can take place
•3. HYPOTONIC – amount of
water inside the cell is less
than outside of the cell.
(CELL EXPANDS)
98%
98% 98%

98%
93%

8. Osmosis & Cell Wall
•Cell wall is a rigid
membrane, how is it
affected by osmosis?