Candy DNA

by Bailey Bergman

This activity guide was developed as part of the Latham Science Engagement Initiative at the University of Iowa.  Directions adapted from https://www.thoughtco.com/make-dna-model-out-of-candy-608201

And https://teach.genetics.utah.edu/content/dna/HaveYourDNAandEatItToo.pdf

Activity Description:

DNA is the building blocks of who we are as people. To understand how it works, one has to be able to understand its structure.  This activity uses candy as models for the structure of DNA and aid in the learning of base pairing. 

Suggested Age Group:

6th, 7th, and 8th grades

Learning Goals:

1. Be able to explain what DNA is and what it does in our body
2. Understand the double helix structure of DNA
3. Learn what base pairs are and why they are important

Materials List:

1. Paper to print instruction on
2. licorice
3. Colored marshmallows or gummies (Four colors needed), presorted into colors
4. Toothpicks
5. Paper plates
6. Completed model for reference
7. Image of correct sequences

Background Information: Basic knowledge of what DNA is and what it is doing in our body is important to know before starting this activity.  If the students know what the shape of DNA is that is great but that can be taught through this lesson

Vocabulary To Know

• DNA
• Sequence
• Base pairs
  • A,T,G,C
• Double helix

Procedure:

• Preassign colors of candy to each base. Example: A=red, T=yellow, G=green, and C=blue
• Introduction: Give background information on DNA structure and base pairing
  • Ask the students if they know what DNA is and how it is structured.
  • Ask them if they have heard of base pairing.
  • Explain if they do not know.
• Making the DNA: Explain to participants the procedure first

1. Choose one of the following sequences
   1. Sequence 1: TACATAAAC 
   2. Sequence 2: T G G T T T A G A A T T 
2. Find colored candy to match the bases and line up sequence
3. Press candy onto a toothpick and slide to the end
4. Attach pointy ends of the toothpicks into the licorice
5. Find correct base pair and add to toothpick
6. Attached other end of toothpick to second piece of licorice to create a latter
7. Twist to create double helix shape

Time Breakdown

• 2 mins: Explain DNA and base pairing
• 2 mins: Explain how to put together DNA
• 5 mins: Assemble DNA
• 2 mins: Wrap up and discussion questions

Discussion Questions:

• What makes up DNA?
• Why is base pairing important?
• What would happen if the bases paired wrong?
• What would happen if the sequence was changed?