Download Tonicity

Describes the ability of a
solution to cause a cell to
gain or lose water. It
depends on the
concentration of a solute.
Solutions
• Remember that a solute is dissolved into a
solvent to make a solution.
Solute
+
Solvent

Solution
Types of Solutions
• There are 3 types of solutions. This is based
on a comparison of the concentration of
solute (the part being dissolved) in each.
Imagine placing a cell into a solution and
comparing the concentrations of solute in both.
Solution
Cell
Types of Solutions
1) Isotonic Solution – The concentration of
solute and water in the cell is equal to outside
the cell. Water is moving = into and outside of
the cell, EQUALLY!
Draw and label the pics.
Solution
Normal in
animal cells
Cell
Flaccid (not firm)
in plants
In each of the following solutions, osmosis takes
place. Remember this rule:
WATER FOLLOWS SOLUTE,
=SOLUTE SUCKS
Remember: Solute Sucks
draw and label the pics in your IAN
Types of Solutions
2) Hypotonic Solution – concentration of solute is
less and water greater outside the cell. Water
will follow the solute and move into the cell to try and
create a balance, equilibrium, homeostasis. The cell
will swell up.
Cell
An animal cell will undergo
cytolysis=lysed=burst
(draw, label pics)
A plant cell has a cell wall so it
will not burst, but will be come
very TURGID, they swell and
are firm, Normal for plants.
Types of Solutions
3) Hypertonic Solution – The concentration of
solute is greater and concentration of
water is less outside the cell. Water will
move out of the cell to try and balance the
concentrations so the cell will shrivel.
Cell
An animal cell will undergo
crenation (shriveling)
(draw, label pics)
A plant cell has a cell wall that
remains the same but the
cytoplasm will shrivel inside the
cell membrane, which is called
plasmolysis (plasmolyzed).
Types of Solutions
flaccid