Here is a one paragraph response applying osmosis to food preservation: Many foods are preserved using osmosis. For example, jam and jelly are made by cooking fruit with a high concentration of sugar. The sugar solution becomes hypertonic to the fruit cells. When the fruit is placed in the sugar syrup, osmosis occurs - water moves out of the fruit cells and into the hypertonic sugar solution by diffusion, causing the fruit to shrink and preserve. This process prevents microbial growth that could cause spoilage, allowing the jam or jelly to be safely stored on the shelf for extended periods. The high sugar concentration draws water out of any microbes that may be present as well, inhibiting their ability to grow and cause foodborne

1. AWESOME
OSMOSIS
AN EGGS-TRA
SPECIAL EDITION

2. Do you
Remember?
_If_U__O_
MOVEMENT OF PARTICLE FROM AREA OF
HIGHER CONCENTRATION TO LOWER
CONCENTRATION

3. Do you
Remember?
DIFFUSION
MOVEMENT OF PARTICLE FROM AREA OF
HIGHER CONCENTRATION TO LOWER
CONCENTRATION

4. VERY WELL DONE!

5. Do you
Remember?
_O__EN_R_TI_N
__AD_E__
DIFFERENCE IN CONCENTRATION OF A
SOLUTE WITHIN A SOLUTION

6. Do you
Remember?
COnCENTRATION
GRADIENT
DIFFERENCE IN CONCENTRATION OF A
SOLUTE WITHIN A SOLUTION

7. YOU ARE A ROCK STAR!

8. Do you
Remember?
_A_S__E
_R_N_P_R_
MOVEMENT OF MOLECULES ACROSS A
CELL MEMBRANE THAT DOES NOT
REQUIRE THE USE OF ENERGY

9. Do you
Remember?
PASSIVE
TRANSPORT
MOVEMENT OF MOLECULES ACROSS A
CELL MEMBRANE THAT DOES NOT
REQUIRE THE USE OF ENERGY

10. Do you
Remember?
W does
hat
semipermeable
mean when talking
about a membrane?

11. Part i al l y- Permeabl e M branes
em
• A partially-permeable membrane will allow certain
molecules to pass through it, but not others.
Partially permeable
• Generally, small membrane
particles can pass
through…
…but large
particles cannot

12. Partially-permeable
More free water molecules on membrane
this side of membrane
Water-solute particle
is too large to pass
through membrane
Free water molecules diffuse in this direction

13. DO YOU KNOW?
W do you get thirsty
hy
after eating something
really salty or sweet?
W do you need to drink
hy
water after sweating a lot?

14. LET’S
EGGS-PLORE
THIS!

15. Watch this!

16. What was the membrane
semipermeable to in the starch
experiment?
 In the egg experiment was the
overall movement of water
towards the side of a membrane
with higher or lower solute
concentration?
 W did water move that way?
hy

17. • Osmosis is the diffusion of free water
molecules…
•… FROM a region of high concentration of
free water molecules…
• … TO a region of low concentration of
free water molecules…
• …ACROSS a partially-permeable
membrane…
…until they are evenly spread out.

18. Osmosis
 the diffusion of WATER
across a semi permeable
membrane towards the side
with higher solute
concentration.
 The membrane is not a barrier
to water so it moves to
equalize the solute
concentrations either side of
the membrane.
 Because the membrane is
impermeable to most solutes so
the solute cannot diffuse to
help out with equilibrium.
 So when solutes are
concentrated inside or outside
the cell, it will draw the water
in its direction.

19. AWESOME OSMOSIS

20. Overview of
Lab
Preparation: Put egg into vinegar.
 Why?

21. > Observe egg A and record info
Carefully rub shell off egg
Rinse egg in water and let dry
Weigh egg
Put egg into corn syrup
 Make Hypothesis!
> Observe egg B and record info
Rinse egg in water and let dry
Weigh egg
Put egg in tap water

23. Overview of
Lab
> Observe egg and record info
Let egg dry
Weigh egg
Data and Analysis

24. RESULTS
SOLUTION MASS MASS DIMENSIONS DIMENSIONS
BEFORE AFTER
BEFORE AFTER
CORN 94 g 97 g L: 16.5 cm L: 15.5 cm
SYRUP W: 15 cm W: 13 cm
PURE 102 g 59 g L: 15.5 cm L: 18 cm
WATER W:13 cm W: 16 cm

25. EGGS-TRA EXPERIMENT

26. DO THIS!
Draw a picture of a cell in
one of the specific osmotic
solutions, with
explanations as to what is
occurring in the molecular

27. VISUAL EXAMPLES
Solution is HYPOTONIC to cell.
Cell is hypertonic to solution.
Solution is HYPERTONIC to cell.
Cell is hypotonic to solution.
Solution is ISOTONIC to cell.
Cell is isotonic to solution.

29. Osmotic solutions
 HYPERTONIC SOLUTION - a solution with a HIGHER solute
concentration than what it is compared with.
 [Hyper = More than]
 HYPOTONIC SOLUTION - a solution with a LOWER solute
concentration than what it is compared with.
 [Hypo = Less than]
 ISOTONIC SOLUTION - a solution with an EQUAL solute
concentration to what it is compared with.
 [Iso = The same as]

30. Sugar syrup Water Egg whites
More concentrated More concentrated Same concentration
solution OUTSIDE cell solution INSIDE cell inside and outside of
cell
Less concentrated Less concentrated
solution inside cell solution outside cell (CONTROL)

31. Egg Osm osi s Lab
Revi ew
What happened t o t he egg i n t he s yrup?
Why?
hy
The water molecules inside
were closer together…
than those outside
So they encountered the
membrane more often
This kind of solution Hyper = Too much
is called Hypertonic Tonic = Solute
“Sugar”
“Salt”

32. What happened t o t he egg i n t he pure w er?
at
W ?
hy
The water molecules outside
were closer together…
than those inside
So they encountered the
membrane more often
This kind of solution Hypo = Too little
is called Hypotonic Tonic = Solute

33. GET A CLUE!
Cyto = cell
Plasm = fluid, or blood
Lysis = to break
Cytolysis = cell breaks: (swells and bursts)
Plasmolysis = fluid breaks: cell shrivels
Which is caused by a hypotonic solution?
hypertonic solution?

34. Remember this:
Hypertonic = t oo much sugar or sal t
Hypotonic = t oo l i t t l e sugar
or sal t
Isotonic = equal sugar or
sal t
Cytolysis cel l br eaks:
= ( swel l s and bur st s)
Plasmolysis = f l ui d br eaks: cel l
shr i vel s
Turgor = W er pr essur e i nsi de a
at
cel l havi ng wal l s
Cytolysis does not happen when a cell has cell walls
Plant & bacteria cells develop Turgor Pressure

36. Osmosis and Red blood cells

38. Osmosis Happens!
 Living things invest a great deal of effort [Energy]
[?] to counteract Osmosis.
 Cells use energy to maintain the balanced
equilibrium of the cell [homeostasis] by actively
moving molecules across cell membranes thus
avoiding cells “drying out” or “exploding”.
 Osmosis is why:

you get thirsty after eating something really
salty or sweet.

why you cant drink seawater when shipwrecked.

why you need to drink water after sweating a
lot.

39. DO YOU KNOW
NOW?
W do you get thirsty
hy
after eating something
really salty or sweet?
W you need to drink
hy
water after sweating a lot?

40. EVALUATE
1. Does the water move by osmosis towards
the hypertonic or hypotonic side of a
semipermeable membrane?
2. In a short sentence explain why osmosis
occurs.
3. If a cell is placed in hypertonic solution,
will it shrink, swell, or stay the same size?
4. If a cell is placed in hypotonic solution,
will it shrink, swell, or stay the same size?
5. W a one paragraph response to the
rite
following question, in order to apply

41. ASSIGNMENT
Explore how osmosis applies in food
preservation process. Give an example of a
food product.