Students reinforce their knowledge that DNA is the genetic material for all living things by modeling it using toothpicks and gumdrops that represent the four biochemicals (adenine, thiamine, guanine, and cytosine) that pair with each other in a specific pattern, making a double helix. They investigate specific DNA sequences that code for certain physical characteristics such as eye and hair color. Student teams trade DNA "strands" and de-code the genetic sequences to determine the physical characteristics (phenotype) displayed by the strands (genotype) from other groups. Students extend their knowledge to learn about DNA fingerprinting and recognizing DNA alterations that may result in genetic disorders.

Learn about DNA. Deoxyribonucleic acid is the blueprint for all living things, but it is so small we can’t usually see it. The role of DNA is to provide our cells information on building proteins; these proteins lead to our individual traits such as eye color, height, dimples, and so much more. The structure of DNA is a double helix and we can model this structure at home. This model is based on the work of Rosalind Franklin, a British Chemist who created an X-ray photograph that provided evidence of the double-helix structure of DNA molecules. We can also extract DNA from a living thing, such as a strawberry, at home. The components of this DNA are so small that it does not look like our model; however, with technology scientists can both see the structure and manipulate the structure to change proteins in organisms. The key concepts and terms explored in this episode include DNA, nucleotides, genes, and genetically modified organisms (GMO's).

As a class, students work through an example showing how DNA provides the "recipe" for making our body proteins. They see how the pattern of nucleotide bases (adenine, thymine, guanine, cytosine) forms the double helix ladder shape of DNA, and serves as the code for the steps required to make genes. They also learn some ways that engineers and scientists are applying their understanding of DNA in our world.