Resources Tab: There are 20 Amino Acids that compose proteins. Nine of them are essential to the human diet. Glycine is the simplest amino acid. You should be able to recognize them from their names since most amino acids end in –ine. All amino acids contain 3 parts, an amino group NH 3 + ), a carboxyl group (COO - )and an "R" group. The "R" group varies among amino acids. The chemical and physical properties of their side chains determine their characteristics. Acidic Amino Acids have amino groups in their side chains that are negative in charge. Basic Amino Acids have amino groups in their side chains that are positive in charge. A protein is created when a series of amino acids are bound together. In proteins, amino acids are joined by peptide bonds in a dehydration synthesis reaction. The function of proteins depends on how many amino acids and what type of amino acids are joined together. When 2 Amino Acids are positioned so that the carboxyl group of one is adjacent to the amino group of the other, an enzyme can cause them to join by catalyzing a dehydration reaction. The chain with the amino end is called the N- Terminus, and the carboxyl end is called the C- terminus.

C O H N Sulfur Mouse over spheres—information and highlight or circle around scientific notation. O = This carboxyl group is at the acidic end. C = This carboxyl group is at the acidic end. a = The central atom is the alpha carbon H = Hydrogen is only one of the many side chains Glycine

Mouse over spheres—information and highlight or circle around scientific notation. B = The beta carbon starts the side chain

Sulfur