An enzyme is a globular protein found in living organisms that acts as a biological catalyst, accelerating reactions that occur in the body without being consumed and using ATP. This means that an enzyme can be used over and over indefinitely ("Enzyme and Substrate | Bioninja"). Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay Enzymes react with substrate by having an “active site,” which is the site where a specific substrate attaches to the enzyme. Upon adhesion to the substrate, an enzyme-substrate complex is formed, whereby the enzyme catalyzes the reaction to form the enzyme-product complex. The product is then released from the enzyme and the enzyme can continue to catalyze the reactions ("Enzyme catalysis | Bioninja"). Enzymes are substrate specific; this means that only a specific enzyme can catalyze a specific substrate. Enzymes are incredibly important for biological functioning, as they are involved in many processes throughout the body to ensure survival. For example, enzymes are heavily involved in the digestive process, where enzymes such as amylase, protease, and lipase respectively break down starch, proteins, and fats into smaller molecules for absorption to occur. Without these enzymes we would not receive the nutrition we need to survive ("Chemical digestion | Bioninja"). Yeast contains the enzyme catalase, which is produced in the body's liver and breaks down hydrogen peroxide. Hydrogen peroxide is a waste product of metabolism and is toxic to the body. In order for the body to get rid of hydrogen peroxide, catalase is produced to break down hydrogen peroxide into aquatic oxygen ("The Health Benefits of Catalase"). Temperature, pH level and substrate are essential factors for enzymatic function; at the optimal level, the enzyme will function at its maximum. If the optimal level is exceeded, the enzyme rapidly denatures, whereby the proteins present within the enzyme are altered and the substrates are no longer able to bind to the enzyme, causing a rapid decline in the reaction rate . The temperature allows an increase in the kinetic energy available for the enzyme to move and collide with the substrate molecules. Please note: this is just a sample. Get a custom paper from our expert writers now. Get a Custom Essay High temperatures cause destabilization of the enzyme and destroys the hydrogen bonds within the enzymes, thus denaturing the enzyme. pH alters the solubility of proteins and changes the overall shape of the enzyme, so the enzyme must be in a solution with the correct pH, otherwise it will not be able to catalyze the reaction. The concentration of the substrate increases the rate of the reaction due to the increase in the number of substrate molecules with which the enzyme can collide. The rate of the reaction will increase until the enzyme reaches the saturation point, where it functions at its optimal level ("Enzyme Activity | Bioninja").