Task 1 In-depth experimental investigationFactors affecting enzyme actionFocused question:This lab will focus on the research question, what pH level has the effect most effective on the activity of the enzyme pepsin (protease) in the degradation of the substrate, albumin. As catalysts, the true function of enzymes is to reduce the activation energy of the reactions they catalyze” (Ward, Tosto, McGonegal, & Damon, 2007). Enzymes are globular proteins that have an overall 3D structure. (George, 2014). Glands in the mucous membrane of the stomach make and store an inactive protein called pepsinogen. Pepsin is secreted in an inactive form because it is an enzyme that digests proteins, preventing the gastric gland from being destroyed by its own enzyme through self-digestion (Roberts, Reiss, & Monger, 2000). This inactive protein is retained in its zymogen (inactive) form until it is secreted into the gastric fluids of the stomach, where it is exposed and activated by hydrochloric acid, as well as by pepsin itself. even in the form of an autocatalytic reaction (Ward, Tosto, McGonegal and Damon, 2007). Once secreted, the mucosa lining the inside of the stomach prevents the functional enzyme from attacking cells (Roberts, Reiss, & Monger, 2000). When food is digested, the food is pushed toward the stomach by a consecutive series of smooth muscle contractions called peristalsis. Once food is in the stomach, it is held for a period of time in order to mix with gastric juice (Cleveland Clinic, 2013). Gastric juice is a moist secretion containing hydroc...... middle of paper ......tly. The enzyme and substrate form a reaction intermediate, and the reaction requires less activation energy than the reaction between reactions without a catalyst present. (Royal Society of Chemistry, 2004). The optimal pH of pepsin is 2.0 due to the lock and key theory and collision theory which is most reactive in this highly acidic environment. This provides the necessary pH that maintains the form or properties in its most practical state so that the reaction can be undertaken successfully in a shorter period of time. Therefore, if pepsin is placed in various pH environments of 0.5, 1, 1.5 and 2 molar HCL and the substrate, albumin is added to each pepsin test tube, then pepsin placed in 2.0 molar HCL will produce the maximum amount of enzyme. activity, because this is the optimal pH of pepsin.