Transcript Tonicity - cypresswoodsbiology

Tonicity is a measure of the osmotic pressure (as
defined by the water potential of the two
solutions) of two solutions separated by a
semipermeable membrane.

Concentration- The
amount of solute per
unit of solvent.
 Osmosis
is the flow
of water down the
concentration
gradient (from an area
of high concentration to
an area of low
concentration)
Water never stops moving, even when
equilibrium has been reached.
 The
net movement of
water across the
semipermeable
membrane is equal.
 The amount of water
entering a cell is the
same as the amount
leaving the cell
 Isotonic Plant cells are
Flaccid.
Water never stops moving, even when
equilibrium has been reached.
There is more substances
than water inside the cell.
The concentration will try to
even out.
 Water will enter the cell.
This causes the cell to swell
(get larger) until it may
burst.
 Hypotonic Plant cells are
Turgid.
 The Process of swelling
animal cells is called
hemolysis

PUTTING A CELL IN PLAIN
WATER
 There
is less substances
than water inside the
cell. The concentration
will try to even out.
 Water will leave the cell.
This causes the cell to
shrink (get smaller)
 Hypertonic Plant cells
are Plasmolyzed.
 The Process of shrinking
animals cells is called
crenation
PUTTING A CELL IN SALT
WATER
Concentration
Water
of
(outside of
Solute (outside
cell)
of cell)
Net
End
Movement Product
Isotonic
Same as
cell
Same
as cell
None
Hypotonic
Less than
cell
More
Cell gains
than cell water
Swells,
turgor
pressure
Hypertonic More than
Less
Cell loses
than cell water
Shrinks
plasmoly
sis
Tonicity
of
Solution
cell
None
 http://highered.mcgraw-
hill.com/sites/0072495855/student_view0/c
hapter21/animation__hemolysis_and_crenati
on.html
 Lets watch a clip and answer questions about
red blood cells in different solutions.