Classification

Amino acids are composed of carbon, hydrogen, oxygen, and nitrogen. On the formula diagrams below, there is a carbon atom at each bend in a line. Each of those carbons has 4 bonds around it, represented by the short dashes between chemical symbols. Two dashes represent a double bond. The hydrogen atoms are understood to be there and are not shown in the diagram for simplicity.

The name of each amino acid is printed in red with a three-letter abbreviation in blue.

1. With a partner, ask your science facilitator for a printed picture of amino acids below. Do not print this page.
    
2. Cut out each amino acid.
    
3. Arrange the amino acids into a classification system based on structural similarities of the 20 amino acids.
   • Consider all 20 amino acids to be in the same Order.
   • Divide this order into Families.
   • Divide each Family into Genera.
   • Each amino acid in a Genus will be a Species. Describe the trait that identifies each Species.
    
4. When you are satisfied with your classification system, paste the members of each Family onto a piece of printer paper.
   • Write the Family characteristic at the top of each page.
   • Paste each Genus in a vertical column on the page with the Genus characteristic at the top of each column.
   • Write the Species trait below each amino acid.