Functions in movement, transport, fighting infection. Contains the carboxyl and amino groups. Monomers are amino acids. There are over 20 amino acids. The order and number of the amino acids dictates the type of protein.
Enzymes are one of the most important types of proteins.
Enzymes lower the activation energy of the reaction. The enzyme contains a site on its molecule called the active site. It holds the chemical being broken up, called the substrate . The enzyme bends the substrate, reducing the amount of activation energy thus allowing the substrate to split fairly quick. Enzymes are specific and can only work on certain molecules.