Making DNA models can be informative, fun, and in this case tasty. Here you will learn how to construct a DNA model using candy. But first, what is DNA? DNA, like RNA, is a nucleic acid that contains the genetic information for the reproduction of life. Its shape is that of a double helix and its appearance is somewhat of a twisted ladder or spiral staircase. DNA is composed of nitrogenous bases (adenine, cytosine, guanine and thymine), a five-carbon sugar (deoxyribose), and a phosphate molecule.
Time Required: 20 minutes
- Gather together red and black licorice sticks, colored marshmallows or gummy bears, toothpicks, needle, string, and scissors.
- Assign names to the colored marshmallows or gummie bears to represent nucleotide bases. There should be four different colors each representing either adenine, cytosine, guanine or thymine.
- Assign names to the colored licorice pieces with one color representing the pentose sugar molecule and the other representing the phosphate molecule.
- Use the scissors to cut the licorice into 1 inch pieces.
- Using the needle, string half of the licorice pieces together lengthwise alternating between the black and red pieces.
- Repeat the procedure for the remaining licorice pieces to create a total of two stands of equal length.
- Connect two different colored marshmallows or gummy bears together using the toothpicks.
- Connect the toothpicks with the candy to either the red licorice segments only or the black licorice segments only, so that the candy pieces are between the two strands.
- Holding the ends of the licorice sticks, twist the structure slightly.
- When connecting the base pairs be sure to connect the ones that pair naturally in DNA. For example, adenine pairs with thymine and cytosine pairs with guanine.
- When connecting the candy base pairs to the licorice, the base pairs should be connected to the licorice pieces that represent the pentose sugar molecules.
What You Need
- Red and black licorice sticks
- Colored marshmallows or gummy bears