Fermentation and Cellular Respiration
How will Temperature Affect the Rate of Fermentation?
Biology Lab 121
November 21, 2013
Partner: Courtney Sargent
Professor: Dr. Marietta Wright
Fermentation is a process that yeast uses to make carbon dioxide. This occurs in an anaerobic setting filled with fluid (Vullo and Wachsman, 2005). This type of fermentation produces energy. Through glycolysis some of glucose is broken down, but the molecule that is formed cannot go into the Krebs cycle. Instead, it enters another pathway that does not utilize oxygen. This pathway produces 2 molecules of ethanol and 2 molecules of carbon dioxide. Fermentation does not ...view middle of the document...
Materials and Methods:
The first step of the lab was to gather the initial materials: 1000ml beaker, graduated cylinder and a water bath. The cylinder was filled with water from the sink and was put into the beaker. The water bath needed to be warmed to 43-46 degrees Celsius. For this experiment there was 3% glucose and 1% regular yeast, both required to be added into the beaker of water. First, 3 grams of glucose was measured out by using a plastic weighing dish and metal scoop. The glucose was added to the water and stirred. Then 1 gram of regular yeast was added into the solution. The glucose and the regular yeast were stirred until there were no clumps left. When the ingredients were fully mixed together, they were transferred into a plastic container, one that can be put into hot water. A manometer was then put on top of the plastic container and then tightened. The container was then placed into a beaker on a hot plate. The thermometer that we used to test the water at the beginning was then needed to be strapped to the side of the container. Before it could be lowered into the water a bubble counter was then attached to the neck of the manometer so that the bubbles could be counted and recorded. Once everything was ready, the plastic container was lowered into the water. At 5 minute intervals, for 30 minutes, we had to record the bubble count and even while we waited we had to monitor the overall temperature of the beaker.
Tables and Graph:
Figure 1: This graph describes the individual bubble counts of the control group and experimental groups.
Figure #2: This bar graph describes the bubble count at the end of both experiments. The control group ended with a count of 182 and the experimental ended with a count of zero.
For the experiment performed, the control group had a greater outcome. Figure 2 states the overall total of the bubbles produced through the experiment. When the control experiment was performed the bubble count was 182 for the 30 minutes. While, for the experimental part performed there were zero bubbles counted. Over time the bubble count increased for the control group, while the experimental group stayed at zero bubbles this is represented in figure one.
Discussion and Conclusion:
For the experimental exercise of this lab the...