1. José Gerardo Cruz Rivera804-10-1716<br />Biofuels<br />Determine the Reaction Rate in the Presence or Absence of an Enzyme<br />The workshop given by Dr. Chiesa was about a typical protein that acts as a catalyst , speeding up chemical reactions that would take far too long to occur on their own. In general, enzymes speed up the vast majority of the chemical reactions that occur in cells. Reactions that break down molecules and those that build up molecules all require enzymes. Each type of enzyme has a specific shape that compliments the structure of its substrate. The substrate is the molecule or molecules that the enzyme converts into a product. Many chemical reactions that speed up can occur at a much slower rate without the enzymes. Enzymes speed up reactions by positioning the substrates and adjusting their bonds so that they become unstable and reactive. In this laboratory, we studied the enzyme cellobiase . Cellobiase is involved in the last step of the process of breaking down cellulose, to glucose. Cellulose is a molecule made up of bundled long chains of glucose that are found in plant cell walls. The natural substrate for the enzyme cellobiase is cellobiose, it is a disaccharide composed of two beta glucose molecules. <br />The purpose of this laboratory is to know the reaction rate in the absence of an enzyme and the amount of this absence at different times. The results are: 1 min- 0.221 absences, 2 min- 0.384 absences, 4 min- 0.733 absences, 6 min- 1.006 absences and 8 min- 1.291 absences. These results demonstrate that as more time had passed, the enzymes had greater absence. <br />