Common Biology Lab
Name____________________________
Osmosis Inquiry
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
Part One: How does particle size affect diffusion and 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
 Sucrose/starch solution
 Distilled water
 Glucose test strips
 Iodine solution (IKI drops)
 Digital balance
*Anticipated time to see results = 15-20 minutes.
Create a procedure that shows osmosis using the materials above:
What do you anticipate observing?
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What did you actually observe during the lab? Record your observations.
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Part Two: Part 2: How does the concentration of a solute affect 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
Common Biology Lab
Name____________________________
Osmosis Inquiry
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
*Anticipated time to see results = 15-30 minutes (all need to be pulled out at the same
time!!!!)  Why?
________________________________________________________________________
________________________________________________________________________
Create a procedure that shows osmosis using the materials above:
What do you anticipate observing? What types of measurements will you be taking?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
What did you observe during the lab? Create a data table to record your
measurements. Once the table is complete turn the data into a graph!
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Submit Formal Lab Report:
Osmosis Lab
Part 1: How does particle size affect diffusion and osmosis?
Part 2: How does the concentration of a solute affect osmosis?
Introduction
 Purpose: What were you testing in part 1 of the experiment? What were you
testing in part 2 of the experiment?
 Background: What did you need to know about osmosis, diffusion, concentration
of solutions, and the properties of a cell membrane to fully understand the
concepts that were covered in both parts of this lab?
o Paragraph 1 – Focus on Part 1
 Information on properties of cells
 What is dialysis tubing and how does it work?
 What is the purpose of iodine and glucose test strips in the
experiment?
 What is glucose?
 What is osmosis? Diffusion?
 Which types of molecules would you expect to diffuse readily?
o Paragraph 2 – Focus on Part 2
 What is the solute and solvent being used in our lab?
 What does concentration mean?
 Which sugar solution in part 2 of the lab has the greatest concentration?
The least?
 What is the manipulated variable and the responding variable in
the experiment?
 What factors determine the rate of osmosis?
Common Biology Lab
Name____________________________
Osmosis Inquiry
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
 Hypothesis: What did you think would be the results of part 1 and part 2? (You
should have this answered on your worksheets under “What do you anticipate
observing?”)
Materials: Bulleted list of all materials used for part 1 and part 2
Procedures: A new student should be able to follow your procedures for part 1 and part
2 and exactly duplicate your experiments!
 Numbered
 Step by step
 Third person
Data:
 Part 1 – Table of observations
 Part 2 – Table of mass for each sucrose solutions. Include the initial mass, final
mass, change in mass, and percent change.
 Formula to calculate % change in mass:
% Change = Change in mass/Initial mass x 100
Graph: Part 2 - Graph the % change in mass vs. concentration. Use CLASS data NOT
group data for your graph!
Conclusions:
 Paragraph 1
o Restate (briefly) the purpose of the experiment
o Restate (briefly) your hypotheses.
o Was each hypothesis correct? Use your data to support your assertion.
(There should be numbers from your data table embedded in your
explanation.)
o What did the data from part 1 prove? What does this mean about the cell
membrane?
o What did the data from part 2 prove? Explain what this means about
osmosis. Use class data!

Paragraph 2
o What did your graph look like? What does this tell you?
o Why did we use class data for the graph rather than group data?
o How did the amount of water in the “cell” change depending on the
concentration of the sugar solutions inside it?
o Why did the amount of water in the “cell” change depending on the
concentration of the sugar solutions inside it? Explain using concepts
about osmosis.
o What happened in the control setup for the lab?
Common Biology Lab
Name____________________________
Osmosis Inquiry
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival
o What were possible sources of error?
o In what way is dialysis tubing NOT a good model of the cell membrane
(think about all of the different ways in which solutes can cross a cell
membrane?)
Common Biology Lab
Name____________________________
Osmosis Inquiry
SLE A1: Lab Report
GSE: LS1-1 All living organisms have identifiable structures and
characteristics that allow for survival