Education Standards
Jelly Marbles
Overview
Students will investigate the process of diffusion through a semi-permeable membrane.
Standards
B.2.2-Describe the structure of a cell membrane and explain how it regulates the transport of materials into and out of the cell and prevents harmful materials from entering the cell.
Learning Objectives
Students will investigate the process of diffusion through a semi-permeable membrane
Students will observe and be able to describe osmosis
Students will hypothesize what will happen when salt is added to the beaker
Materials
10 Clear Jelly Marbles (can be ordered from stevespangler.com),
Clear Orbeez, or DecobeadsWater(read directions from type of above ordered as some amounts of water vary)
4 beakers
Food coloring
Salt
Student worksheet
Extension options: Ice, Hotplate
Procedure
1.Recommended for students to work in groups of 2-3
2.Put all necessary materials on each table (you can decide you add the food coloring or leave it on the tables depending on how much dye you have available)
3.Have students observe the jelly marbles(This will take some time)
4.Add all 10 jelly marbles to a beaker and add water (40mL)
a.Watch a short clip about cell transport during this time
5.Afterjelly marbles have grown have students either hypothesize and/or describe what happened (this is dependent on whether it is an intro of follow up lesson to cell transport)
6.In a separate beaker add 40mL of water –add 2-5 drops of food coloring, add 5 of the jelly marbles from beaker 1
7.After jelly marbles have changed color have students either hypothesize and/or describe what happened (this is dependent on whether it is an intro of follow-up lesson to cell transport)
8.In a 3rdbeakerfill with 40mL of water add 5 of the jelly marbles from beaker 2
9.Have students hypothesize if they think the color will diffuse back out of the marble
10.In the 4thbeaker fill with 40mL of water and add salt until saturated –add 5 clear jelly marbles from beaker 1
11.Have students hypothesize what will happen when the marbles are added to a salt solution –what process does this describe
12.Extension –test different ways to make the diffusion happen faster –does the water temperature affect the rate of diffusion?
13.How could you make a hypotonic solution with the jelly marbles
14.Have students relate this to cells, cell membrane, osmosis, diffusion, hypotonic, hypertonic, isotonic etc
Credits
This learning module was created by Bridgette Drake, a participant in Indiana University-Purdue University’s NSF-Funded “Nanotechnology Experiences for Students and Teachers (NEST)” Program (Award # 1513112).