10.12.10 – Turgor Pressure Lab Day 1
• OBJ: The students will prepare potatoes for
our lab tomorrow to observe turgor pressure.
• TEK 7.7c
• Warm up: Explain in your own words or draw
someone or something using forces from not
doing work to doing work.
– For example, a car not moving  to moving  to
being hit by another car  to coming to a stop.
QUESTION:
• How will a salt solution affect the potato slices?
Materials:
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Salt solution
Raw potato fries
Distilled water
100mL beakers
Research – Turgor Pressure
Research –Turgor Pressure
• Turgor pressure is the pressure exerted against
the cell wall by contents of the cell.
• Turgor pressure is important for plant support
and maintaining shape
• Seeds sprout because the force of water
pressure inflates the emerging shoot. The
force of the shoot straightening pulls the seed
leaves above ground.
Procedure
• Day 1:
– Cut a raw potato into French fries.
– Soak one class set of fries in salt water and
another in fresh water.
• Day 2:
– Distribute one of each fry to lab groups. Make
observations.
– Bend each fry to the breaking point and record
the differences between the two.
• Recall: Salt solution will shrink; distilled water
solution will become turgid
• Summary: Turgor Pressure is ____________ .
• Out: Test on Friday!!!
10/13/10 – Turgor Pressure Lab DAY 2
• IN:
– Objective: The students will demonstrate the
effect of turgor pressure on potatoes using a
laboratory aid.
– TEKS: 7.7C
– Warmup: Reflect on yesterday’s research and
explain and draw turgor pressure.
Research - Equilibrium
• When net forces equal zero, or there is no
movement in a system, a state of equilibrium
has been reached.
Forces in Living Systems
• The teeth apply force in breaking food into
smaller pieces
• Muscles in the esophagus exert a force in pushing
food down the digestive tract through peristalsis
• Muscles contract and relax, creating a enough
force to move bones to walk, run, jump or engage
in other life processes
• The heart supplies the force that causes blood to
flow through blood vessels.
Day 1 Reflection
• Question: How will a salt solution affect a
potato?
• Procedure:
– Cut a raw potato into French fries.
– Soak one class set of fries in salt water and
another in fresh water.
• Day 2:
Day 2 Procedure
– Distribute one of each fry to lab groups. Make
observations.
– Bend each fry to the breaking point and record
the differences between the two.
Hypothesis:
• If we put the potato slice in… then… because…
Experiment:
Potato type:
Potato is salt
water
Potato in regular
water
Observations:
Analysis:
1. What did you notice about the potato in the
salt water?
2. How did this happen?
Conclusion: summary
Tell me if your hypothesis was valid or invalid.
Explain why!
• Recall: Equilibrium is ___________.
• Summary: conclusion
• OUT: Think about what the salt water did to
the potato… what do you think happens to
your body when you eat too much salt?
10.14.10 REVIEW
• IN
– OBJECTIVE: The student will review the last three
weeks material using informative stations.
– TEKS: 7.7A,B,C
– Warmup: Define force. Define work. Define power.
How are the three related?
REVIEW STATIONS
• Classroom is organized into groups. Stay
within your groups
• Have 6 minutes with each informative
paragraph
• Answer questions on study guide related to
the paragraph you have.
• When music stops and time is up, you will
switch your cards with another group.
• RECALL: Chemical energy is transformed into
thermal energy in digestion.
• SUMMARY: Tell Fred how you will study for
the test.
• OUT: Describe in two sentences a force seen
within living things.
10.15.10 TEST
• IN:
– OBJECTIVE: The students will assess their
knowledge of the last three weeks by taking a test.
– TEKS: 7.7 A, B,C
– Warmup – Study briefly.