In the cells that make up our bodies, thousands of different chemical reactions which keep us alive are constantly taking place. Together, these reactions make up our metabolism, converting the wide variety of chemical compounds that we consume into the chemical compounds that we need. Each chemical reaction is helped along by a specific protein catalyst called an enzyme . As catalysts , enzymes increase the rate at which specific chemical reactions take place. But in the process, the enzyme itself remains unaltered.
Enzyme catalysts are amazingly specific and efficient.
Compare that with a chemist attempting to synthesize a particular compound in the laboratory. Each step is catalyzed by a specific enzyme. The sequence of steps by which one molecule is converted to another is known as a metabolic pathway . The explanation lies in the study of genetics , the scientific study of heredity. The structure of each enzyme is determined by a specific gene , part of the hereditary material which exists in every cell in our bodies.