The Genetic Code: A Hands on Activity

School of Government Ana Alea’s Biology class recently concluded an experiment that integrated the study of DNA, RNA, and protein synthesis with an enjoyable craft project.

In this activity students were given written examples of DNA strands.  DNA consists of a series of nucleotides (adenine, guanine, cytosine and thymine).  Following the rules of transcription, the students produced an mRNA strand.  This mRNA strand contains the genetic code for eight characteristics of a simple imaginary organism. 
Using thei mRNA strand and a teacher-supplied chart, the students translated the nucleotides of their strand into a chain of amino acids.  Each group of three nucleotides constitutes a "codon" that codes for a specific amino acid.  

The students were then provided with the materials to create a bracelet:  string, scissors, and different colored beads.

Using the beads, the students then assembled bracelets, using as a basis their amino acid chain, in which each colored bead represented a specific amino acid.  The resulting bracelets provided a visible and tangible means of connecting the abstract DNA to a concrete series of proteins.

 Students then turned in all written work, only keeping their bracelets.  They were then were given a chart, in which each group of three amino acids manifested as a specific characteristic in their imaginary eight-trait organism.  For example, the amino acid sequence, serine-proline-isoleucine gave the organism a tail, while the sequence glycine-alanine-alanine resulted in no tail.

Using their bracelets only, the students decoded their amino acid chains and drew their resulting organisms. Any errors in their bracelets represented mutations in their organisms.  Depending upon the severity of the mutation, their organisms might not be viable.  For example, the organism could survive without a tail, but not without a head.  (Some students were so unhappy with their nonviable organisms that they chose to repeat the beading exercise completely!)

Students analyzed their results, determining what type of mutation their organism had (if any)--deletion, substitution or insertion.  Students with errors could write a report explaining, in detail, the error(s) to improve their grades.