Hands-on Biochemistry: Beads, Pipe Cleaners, and the clearest way to teach monomers and polymers!

A few years ago, I looked at my biochemistry unit and tried to think of some way to revolutionize it.  Monomers, polymers, carbohydrates, phosopholipids, amino acids... To my students, these aren't concrete things.  I might as well be speaking Chinese.  I decided they needed a hands-on activity to understand that these are things, actual molecules, substances that make up everything that is alive on earth.  

My mentor teacher used beads on pipe cleaners to teach protein structure.  I think this is a great way to teach them because you can bend the pipe cleaner to form alpha helices, beta strands, and other structures.  The assorted beads are great for showing the variety in amino acids.  So when I was thinking about my unit a few years ago, I thought, why not use beads and pipe cleaners for carbohydrates and lipids too?! 

But carbohydrates are just plain boring.  Sugars look pretty much the same.  The polymers are just... strands of glucose.  They are like amino acids, in that they are like "beads-on-a-string", but they all look the same.  So I chose to represent the monomer monosaccharides with white, yellow, and orange pony style beads.  I do my carbohydrate activity with my students first, before my protein activity, because students can get a simple, basic understanding of monomers and polymers without getting into the protein structure level details.  

The carbohydrate activity is fun for them anyway, even if the beads are "boring".  They don't know how cool protein structures can be, so the carbs are fun at that point.  And a few days later, I introduce the protein activity and the students are in heaven.  

I changed up the traditional protein structure activity by adding in alphabet letters!  By introducing alphabet letters and having students create a word somewhere in their amino acid sequence, I introduce the idea that some amino acids are more important than others in the function of the protein.  The word is the most important part of their protein "bracelet" as many students call them.  Later, when we talk about missense, silent, and nonsense mutations, I re-introduce these!

With my lipid activity, I use pipe cleaner pieces for fatty acids, to contrast them from bead-like monosaccharides and amino acids.  I think it's important for students to see the difference between the long hydrophobic chains and the other macromolecule building blocks.  

*Update: I just created a new activity for nucleic acids!  Click here to read about it*

Using these ideas, you could make your own biochemistry with beads activities!  If you would like to check mine out, you can find them here.  My activities are designed to be completed in student groups of 2 or 3 and take about an hour each to complete.