The genetic code is a set of rules that guide how the sequence of DNA nucleotides is read by a cells machinery and turned into a sequence of amino acids that make up a protein. Incredibly, nearly all living things use the same genetic code!
To understand how DNA provides the instructions for making proteins, one first needs to understand a little about what a protein is. A protein, like DNA, is a polymer (a long molecule that is a chain of smaller repeating subunits). The subunits in proteins are called amino acids. There are 20 different amino acids that can be linked together in an infinite array of sequences of different lengths. These chains of amino acids form the proteins that do all the work in our bodies – building cells, generating energy, transporting materials, and more. For this activity, it is important to note that each amino acids has been assigned a single letter abbreviation which allows students to create protein “words” and “messages” with different sequences of amino acids.