Abstract:
We have tested the affects of increased temperature above room temperature on the rate of fermentation of yeast. We had 6 flasks filled with 6mL DI water, 2mL Yeast suspension and 6mL glucose of which 3 were at 25°C and 3 were at 37°C. The flasks at 37°C had each mixture pre-heated at 37°C for 2 minutes before being combined and then added to the flask where it was put into the bath heated to 37°C. We then checked CO2 levels in each flask every 2 minutes for 20 minutes. We came out results that showed a marginal difference between the amounts of CO2 produced at different temperatures. The results showed that increased temperature causes an increase in fermentation rate and increased production of CO2.
Introduction:
Fermentation is the break down of organic matter, by microorganism, in the absence of oxygen also known as anaerobic (Van Neil, 2008). Our reactions occurs when yeasts is added to a solution of glucose and water. Fermentation starts with a process called glycolysis. In glycolysis Glucose is broken down into two molecules of pyruvate and a net yield of 2 NADH (electron carrier) and 2 ATP (adenosine triphosphate) molecules. The first step of glycolysis is the energy investment phase. In which 2 ATP’s are added to the Glucose molecule, which produces 2 ADP’s and Fructose 1, 6-biphosphate. This is followed by the energy payoff phase. In this phase NAD+ is reduced to NADH and ADP is reduced to ATP. The total number of ATP created is 4 and 2 NAHDH. After the energy payoff phase what is left is 2 pyruvates. Fermentation then takes place only in the absence of oxygen. In fermentation the pyruvate is converted into ethyl alcohol, through the oxidation of the 2 NADH molecules, which returns them to two NAD+’s (Freeman, 2011). Oxidation is the loss of an electron in this case H+. We used information from previous labs in which we tested
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