Observing Osmosis Using Gummy Bears
Background Information: Movement through membranes is called transport. Molecules are in constant motion, and
tend to move from areas of higher concentrations to lesser concentrations. Diffusion and osmosis are passive forms of
transport; this means that they do not need energy to move areas of high concentration to areas of low concentration.
Active transport requires energy to transport molecules from low concentration to high concentration. Osmosis is the
movement of water through a selectively permeable membrane from an area of high concentration to an area of low
concentration.
Purpose: To simulate cell transport using a gummy bear (cell) placed in different types of water solutions.
Question/Problem:
Day 1-2: How will soaking Gummy Bear candies in distilled water affect the size of the candy?
Day 2-3: How will soaking Gummy Bear candies in salt water affect the size of the candy?
Prediction/Hypothesis: (explain your prediction based on the background information – write in your lab
NOTEBOOK). Create a hypothesis for Day 1-2 and a separate hypothesis for Day 2-3. Be sure they are clearly labeled!
*Identify the following in your pre-lab: independent variable, dependent variable, control, and constants
Materials:
Beaker, Water, Gummy bear, Ruler, Electronic Balance, Calculator
Length
Width
Procedure – list procedures so that you could perform the lab WITHOUT this handout.
Height
Day 1
1.
2.
3.
4.
Obtain a cup, a gummy bear and a ruler.
Label the cup with your group's name and class period
Take the mass of the gummy bear.
Measure your bear (in cm) from top to bottom (length), from side to side (width), and from front to back
(height). Record these measurements in your data table.
5. Place the bear in the cup and fill with 40mL of water.
 Place the cup in the designated area for 24 hours.
6. Calculate the volume of each bear (l x w x h).
Day 2
7. Use a plastic spoon to gently scoop out each bear.
BE CAREFUL not to break the bears, they are very fragile.
8. Take the mass of the gummy bear.
9. Measure the length, width, and height and record in your data table.
10. Empty the water out of the beaker.
11. Fill the cup with 40mL of salt water solution.
12. Return the same bear to the cup and return them to the designated area for another 24 hours.
13. Answer pre-lab questions and questions for day 1-2.
Day 3
14.
15.
16.
17.
18.
Use the spoon to gently scoop out each bear.
Take the mass of the gummy bear.
Measure the length, width, and height and record in your data table.
Throw the gummy bear and cup away.
Answer questions for day 2-3 and write your conclusion paragraph.
Data: (create the following table in your lab notebook – use a RULER!!)
Before Soaking in water
After soaking in water
(Day 1)
(Day 2)
Height (H):
After soaking in salt water
(Day 3)
Width (W):
Length (L):
Volume (LxWxH):
Mass (in grams):
Pre-lab questions:
1. What are 2 characteristics that distinguish passive transport?
2. What is the difference between diffusion and osmosis?
3. What part of the cell do materials go through to move into or out of the cell?
4. What are the 3 types of osmotic solutions – describe each and what would happen to a cell in that environment?
Conclusions Questions:
Day 1-2 Questions:
1. What happened to the bears after being initially placed in water? (Look at your Day 1 vs. Day 2
results.) Explain the direction of water movement.
2. Explain your observations in terms of osmosis – what specific type of solution is this and explain.
3. Predict: what do you think would eventually happen if it was left in the water for a few more days?
4. Predict: what will happen when you put the bear in salt water tonight? Explain why.
Day 2-3 Questions:
5. What happened to the bears after being placed in salt water? (Look at your Day 2 vs. Day 3 results.)
Explain the direction of water movement.
6. Explain your observations in terms of osmosis – what specific type of solution is this and explain.
7. Explain any change in color in the bears or their solutions.
8. What does this lab have to do with diffusion, osmosis and the cell membrane?
Conclusion:
Write a paragraph to explain the results of this investigation using the concept of osmosis. Include specific data to
support what you say.