How to Make a DNA Model Out of Food

Deoxyribonucleic acid (DNA) carries the genetic code for organisms, and is a topic of scientific study at many grade levels. Students are often assigned to make DNA models to help them learn about the make-up and structural characteristics of DNA. A DNA model can be constructed with toys, food, candy or common household items. Use a model of DNA to exhibit a sample of nucleotides on a double helix.

Instructions

1

Make pastry dough balls in two colors. Put 14 tbsp. of softened butter into a deep salad bowl. Add 2 cups of all purpose flour and 1/2 tsp. of salt. Blend with a pastry cutter until it forms small crumbles. Add 4 tbsp. of cold water, one at a time and mash with a fork until the dough collects into a ball and cleans the sides of the bowl. Form 30 1-inch balls. Dye the balls with food coloring making 16 one color and 14 a contrasting color.

2

Dye eight plain-colored uncooked penne tubes to create a fourth color for the pasta to represent the DNA chemical bases. Colored penne typically comes in three colors, one being the natural yellow pasta color.

3

Break uncooked spaghetti into 24 4 1/2-inch sticks. Break off another 36 3-inch sticks.

4

Slip two different-colored penne tubes over three 4 1/2-inch spaghetti sticks. Align the penne tubes in the center of the sticks and poke the ends of the sticks into two dough balls of the same color to construct the first rung of the double helix.

5

Set up the spiraling effect for the double helix with slanted rails. Hold two 3-inch spaghetti sticks together and push them through a dough ball of the color not used on the rung. Align the ball in the center of the sticks. Place one end of the spaghetti into a dough ball on the first rung so that it leans slightly forward. Construct another rail with two 3-inch spaghetti sticks and a dough ball and slip it into the other dough ball of the first rung so that it leans slightly away.

6

Build a second ladder rung with the other two colors of penne on three 4 1/2-inch spaghetti sticks between two colored dough balls. Use the same color dough balls as the first rung. Set the second rung on the ladder by piercing the slanted spaghetti sticks of the rails through the dough balls and the ends of the rung. The second rung should be offset so it is not parallel with the first.

7

Use the same color dough balls for all the rung sides, and the other color for all the rails. Continue slanting the rail sticks alternately to make the ladder spiral as it rises.

8

Build the twisted ladder with eight rungs. Stick two 3-inch sticks into the bottom of the dough balls of the bottom rung and stand them up in the remaining dough in the salad bowl for upright support.