Aim: How do Osmosis and
Diffusion compare?
DN: Explain the difference
between passive and active
transport.
HW: Page 199 #33-34
What is the diffusion of
water called?
Osmosis
OSMOSIS
 The
movement of water from an
area of high concentration to an
area of low concentration.
What is meant by concentration?
The amount of solute!
Solvent: The liquid (ex. Water)
Solute: The solid added to the liquid (ex.
Salt/sugar)
Distilled water
100% pure water
Concentration Differences:
1)
A 90% salt solution vs. a 20% salt
solution
Which solution has more salt particles?
Which solution has more water molecules?
2) A 60% salt solution vs. 80% salt
solution?
Which container has a greater
concentration of water molecules?
= Solute (salt)
= Solvent (water)
Which container has a greater
concentration of solute molecules?
In which direction is osmosis going
to occur?
= Solute (sugar)
= Solvent (water)
Selectively Permeable
Why does this happen?
There
is MORE WATER
on the left side of the
membrane so it moves
to the right side.
Why are the water molecules
diffusing to the left?
Water molecules are red
The
water is moving
from an area of high to
low!
Why does water go in and out
of the cell?
EQUILIBRIUM
If soluteTo
is maintain
equal, DYNAMIC
then so is
water amt.,
molecules still move back and forth!
What happens to an animal
cell if it is surrounded by a
high concentration of water?
Water will enter the cell! Cell will swell and burst!
What happens to an animal
cell if it is surrounded by a
low concentration of water?
The Cell will shrink!! Salt sucks!!!!
Summary Questions
Will osmosis happen?
In which direction will
osmosis happen?
How is osmosis a form of
passive transport?
Osmosis is the movement of water from
an area of high concentration to an
area of low concentration. No ATP