Duplicating Chromosomes

Hands-On Activity
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For this activity you need Four paper clips per person Beads of four different colors
Put the beads in a bowl so they don't escape.

We know that the chromosomes that carry our genetic information are made up of four amino acids.

These amino acids connect up with their partners.


<- pairs with  ->



<- pairs with  ->


Use the colored beads to represent the different amino acids. Write the colors here:

 Amino Acid





 Color of Bead        

Create a Chromosome

Gather your materials. You are going to make a model of a chromosome. A chromosome has two strands.

Straighten out two of the paper clips, leaving a hook at one end of each.

Make the first strand:
The beads represent the amino acids.

Put beads on one straightened paper clip.

Bend the other end of the paper clip back.

This is one strand of the chromosome.


Now take the other straightened paper clip.

Put it beside the one that you just finished.

This will be the second strand of the chromosome.

This part is tricky!

Find the partner for each colored bead.and put it on the open paper clip

 Bend the second paper clip to hold the beads.

You have now made the second strand of your chromosome model! Good for you!

Now exchange chromosomes with a partner and check to be sure that the amino acids are paired up correctly.





 Duplicating Your Chromosome

When a cell divides, it has to make copies of the chromosomes in itself. Every cell in the body has copies of the same chromosomes.

Let's duplicate your chromosome the way your body would.

 Straighten out the remaining two paper clips.



Separate the two strands of your chromosome.

Now, think!

Each of these pieces is half of a chromosome, rather like one side of a zipper.

Place each half of the completed chromosome next to a straightened paper clip.

Now, carefully put the partner beads on the empty paper clips.


When all the partner beads are in place, fold up the other end of the paper clips


What do you have now?

How does this process work?

Did you get an exact copy of your chromosome?


You should have two complete, double stranded chromosomes now.

Share your chromosomes with the people sitting near you.

Mix all your chromosomes together and then pick out one. Can you find the other piece of it? Match up your amino acids!

From World Builders: http://curriculum.calstatela.edu/courses/builders/
Copyright © 2000.   Elizabeth Anne Viau and her licensors.  All rights reserved. This material may be used by individuals for instructional purposes but not sold. Please inform the author if you use it at eviau@earthlink.net.