Laboratory 6: Lactase Enzyme Lab Report
March 31, 2014
Enzymes are types of proteins that work as a substance to help speed up a chemical reaction (Madar & Windelspecht, 104). There are three factors that help enzyme activity increase in speed. The three factors that speed up the activity of enzymes are concentration, an increase in temperature, and a preferred pH environment. Whether or not the reaction continues to move forward is not up to the enzyme, instead the reaction is dependent on a reaction’s free energy. These enzymatic reactions have reactants referred to as substrates. Enzymes do much more than create substrates; enzymes actually work with the substrate in a reaction (Madar &Windelspecht, 106). For reactions in a cell it is important that a specific enzyme is present during the process. For example, lactase must be able to collaborate with lactose in order to break it down (Madar & Windelspecht, 105).
Lactase, a type of enzyme usually found in the small intestine, breaks down lactose into sugars such as galactose and glucose. People that are lactose intolerant cannot consume anything containing dairy because they cannot break down lactose, a sugar found in milk. Those that are lactose intolerant lack the enzyme lactase. Without lactase, the body does not have the ability to break down lactose, which leads to a person having an upset stomach and diarrhea. Adults are more likely to be lactose intolerant than children because of the metabolic change in the body (Dritsas). The lack of lactase that people have can be compensated by taking pills to help break down lactose that is consumed; with the help of a lactase pill the body can now absorb galactase and glucose properly (McCracken, 481).
The purpose of the following experiments was to test what exactly the specificity of lactase is and how pH and temperature have an effect on lactase. In order to test the specificity, two substances, milk and sucrose, were added to either water or lactase to test the amount of glucose included in the substances. For the second experiment, three different pH levels of lactase and temperatures were used to test how different environments and pH values affect the activity of lactase. Given the background, we hypothesized that for the first experiment, the lactase will break down lactose in milk and have a similar effect to sucrose. We also predicted that the Milk + Lactase reactant would have more glucose, the Milk + Water reactant would have a little bit of glucose broken down, the Sucrose + Lactase reactant would have less glucose than the Milk + Water reactant, and the Sucrose + Water reactant would have little to no glucose at all. As for the first procedure of the second experiment, we had hypothesized the more basic the solution would become, then the more glucose there would be. Our prediction for the first procedure of the second experiment was that there would be no glucose...