In a classroom at the California Rehabilitation Center in Norco, inmate students had an opportunity to do something “outside the box.” Instead of the usual books, paper, pencils, and calculators, the students used toothpicks, wooden splints, colored marshmallows and red and black licorice to learn about and construct DNA molecules.
I had worried that the lab would be too complicated for my inmate students or that they would struggle to assemble the model or even be bored with the technical concepts but quite the opposite occurred.
Students learned how everyone’s DNA is a unique genetic “footprint,” and how they could make life choices, like using sunblock or not smoking, that would protect them from environmental mutations.
The DNA molecule’s structure was discovered in 1953 by American biologist James Watson and English physicist Francis Crick, who described it as a three-dimensional double-helix structure, a “twisted ladder” in layman terms.
My students successfully created their own DNA models with minimal direction from me and were curious about mutations.
Each DNA strand consisted of various on-hand components: a wooden splint represented the phosphate; licorice took the place of deoxyribose (a sugar); and a marshmallow stood for the nitrogenous base.
Once the strands were made, students coiled two strands around each other and connected them with a toothpick in the center, which represented a hydrogen bond.
The trickiest part of construction was modeling how DNA base-pairing occurs. The students matched specific colored marshmallows with each other just as an actual DNA strand would pair up bases: adenine (A) and thymine (T), and cytosine (C) and guanine (G).
The students even went so far as to illustrate DNA replication using the black licorice to signify newly formed DNA creating a second model from the first, which is how it replicates in our cells.
The class learned that there are mutations, “cute” ones that cause dimples and freckles, as well as “errors,” which can cause cancer. The “errors” occur during DNA replication and can be caused by environmental sources like exposure to too much sunlight (UV radiation),.
Although the word “mutation” has a negative connotation, mutation is the reason for the genetic diversity in the classroom.
There was a lot of laughter and peer collaboration. Students who normally were less engaged or less talkative participated in the activity.
The exercise is proof that teachers in correctional institutions can do STEM (Science, Technology, Engineering, Mathematics) activities using all learning modalities: aural, visual, physical, and so on, so that learning is still interesting and relevant.
The candy model was not quite what the original scientists Watson and Crick probably envisioned, but it proved to be just as valuable when used as a teaching tool.
PPI’s “Correctional Control: Incarceration and Supervision by State” is the first report to aggregate data on all types of correctional control nationwide.
By Sierra Whitney Contributing Writer