Common Biology Lab
Name____________________________
Osmosis
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
Purpose: To observe osmosis using different concentrations of solutions
through dialysis tubing (a model of a cell membrane).
Question: How do different concentrations of sucrose solution affect the
rate of osmosis?
Materials List (use some or all…check the ones you use for your formal lab
write-up!!!)
 Dialysis tubing (8” – 12” long, soaked in water overnight)
 String
 Clear plastic drinking cups
 Sharpie marker
 Funnel
 Distilled water
 1.0 Molar sucrose solution (342g sucrose, 1L water) diluted into 250
mL beakers of 1.0 M, 0.8 M, 0.6 M, 0.4 M, 0.2 M sucrose solutions
 Digital balance
SUBMIT
Introduction:
* For this section of the lab report answer the following questions in
paragraph form:
Paragraph # 1:
 What is the purpose of the lab?
 What is the question you are answering?
Paragraph # 2:
 Provide Background Information on:
o Osmosis in general (including describing the flow of water
during osmosis  the concentration gradient)
o Osmotic Pressure (including background on Hypertonic,
Hypotonic & Isotonic Solutions)
o Dynamic Equilibrium in osmosis
Paragraph # 3:
What is the hypothesis?
Be sure your background information supports your prediction
(hypothesis).
Your prediction should be specific. If you predict a change will
occur, you must specify the type of change you expect to find.
Materials:
 Bullet the materials list
Common Biology Lab
Name____________________________
Osmosis
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
Procedures:
1. Number the steps in the procedure. Each step must be a complete
sentence.
2. Don’t forget to add in the hazards/safety measures taken!
Data/Observations/Graph:
 All tables must have a title (example - Table 1: Sugar/Starch Solution
Data), labeled units, and must make sense!
 The graph must have a title (example - Figure 1: Sugar/Starch
Solution Data), labeled units, a key, and must make sense!
 For calculations  (example: calculating change in mass) give one
example using your data for each different type of calculation
done.
CONCLUSION WRITING GUIDE!!!
CONCLUSION:
* Answer the following questions in paragraph form. Do NOT number
these in your conclusion  Paragraph form ONLY!!!
Paragraph # 1:
1. Restate the purpose and hypothesis
2. Was your hypothesis correct? Use your data to support your
assertion Example: “the hypothesis was correct because there was
a change of 10mg…”
Paragraph # 2:
1. Discuss and explain potential reasons for the differences in change
in mass at specific sucrose concentrations. Use your data (#’s and
graph) to support your conclusions.
2. Which sucrose solution concentration would take the longest to
reach equilibrium and why?
Which sucrose solution concentration would take the least amount
of time to reach equilibrium and why?
Is there any concentration that will never reach equilibrium? Why?
3. How do your results relate to dynamic equilibrium?
Paragraph # 3:
1. When wilted plants are watered, they tend to become rigid. Explain
how this might happen.
Common Biology Lab
Name____________________________
Osmosis
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
2. What would happen to a plant if it was watered with salt water?
Explain your answer.
3. How is the dialysis tubing similar to an animal cell?
4. How is the dialysis tubing different from a plant cell?
5. What may happen to an animal cell if water moves into it? How
does this differ from what would happen in a plant cell? Explain why
they differ.
Paragraph # 4:
1. What could be some sources of error in your experiment?
2. What can you do to improve the experiment if you were to do it
again?
3. What extra/new questions were generated that would lead to a
deeper understanding of the topic?