TURGOR PRESSURE
Lab
What is Turgor Pressure?
Plant cells are very much like your own
cells, except they are surrounded by a cell
wall. This cell wall is part of what gives
plants such a rigid and sturdy structure.
Plant cells need a certain amount of
pressure to make sure that the cell wall
stays rigid, and this pressure is called
turgor pressure.
How It Works
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The way a cell maintains pressure is through a process
called osmosis.
When a plant cell is in a hypertonic solution.
 The
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solute is greater where?
The water from the inside of the cell rushes out to the
surrounding solution, and the cell becomes plasmolyzed.
This is very unhealthy for the cell because it loses not
only its water but also its rigidity and structure, often
causing the plant to wilt.
How It Works
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If a plant cell is placed in an isotonic solution. Water
neither rushes in or out of the cell because the ratio of
solute to solution is the same on both sides of the cell
wall. However, this is still not enough rigidity for the
plant cell, and the cell is flaccid.
When a plant cell is in a hypotonic solution. The water
from the inside of the cell rushes out to the surrounding
solution, and the cell becomes cytolyzed. This is healthy
for the cell because it gains not only its water but also
its rigidity and structure, often causing the plant to stay
strong.
Lab:
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Turn to the next two blank pages in your
notebook and label the left page Turgor
Pressure Lab.
 Add the date and page number, and put it
into your table of contents
Write the first three sections of your
laboratory report
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OBJECTIVE: To explore how force affects turgor
pressure in plants.
BACKGROUND INFORMATION:
Turgor pressure is the pressure, or force of the water
inside a plant cell against the outside, or cell wall. Think
about what happens when a plant is in need of water
and what the plant looks like before and after you
water it. These changes happen because Turgor
pressure changes. There is less force before you water
the plant.
Protocols:
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2.
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10.
Get 2 pieces of potatoes of the same length and size.
Get two petri dishes. Label one A for salt water and the other B
for distilled water.
Obtain the mass of petri dishes A and B.
Place two pieces of potatoes in each petri dish.
Obtain the mass of the petri dishes with the potatoes in them.
Add salt water to petri dish A
Add distilled water to petri dish B
Let potatoes soak for 20 minutes.
When the potatoes are done soaking, dry them with paper
towel and measure their mass and record it in the data table.
Test the firmness of each potato by trying to bend them. Record
your observation in the data table.
Lab Work:
Mass of Petri Mass of Petri
Dish
Dish and
Potato
Salt Water A
Distilled Water B
Mass of
potato
before
soaking
Mass of
potato after
soaking
Firmness of
potato
Results:
1.
2.
1.
What does the amount of bend tell you about
the Turgor pressure inside the potato cells?
What effect did the salt solution have on the
potato?
Which caused greater Turgor pressure inside
the cell - water or salt solution?
Conclusion:
Write a conclusion in paragraph form. The following should be
in your conclusion:
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state the purpose/objective and your original
hypothesis
Very briefly summarize the experiment. State the results,
quote data.
What was the direction of water movement in the
potatoes?
Does the data support the hypothesis? Use actual data to