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.
This is called the form-fit hypothesis. These are complex substances composed of monomers called nucleotides. DNA and various forms of RNA are examples. They function in protein production and heredity.