In Yeast Fermentation, Rates Of Carbon Dioxide Pro

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Intro: Biofuels companies seek to increase the rate of ethanol production through fermentation of Saccaromyces cerevisiae. Fermentation converts sugar to energy, yielding ethanol and carbon dioxide. Ethanol produced from sugar or grain is currently the most common renewable fuel (Hahn-Hägerdal, et al., 2006). Our experiment was conducted in order to determine if increasing the amount of glucose in a yeast suspension would increase the production of carbon dioxide, thus increasing the rate of the reaction. Anaerobic yeast fermentation of glucose will cause a change in pressure in a tube due to carbon dioxide production. This information provided support to develop a method that was sufficient in testing the rate of carbon dioxide production using different amounts of glucose. We hypothesized that by increasing the amount of glucose the rate of carbon dioxide production would increase due to there being more glucose for the yeast to react with. Methods: A solution of 1.5 ml of glucose solution was mixed with 1.5 ml of yeast suspension and drawn into a 5 ml syringe. Another solution was created, but with 3.0 ml of glucose and 1.5 ml of yeast suspension, also drawn into a 5 ml syringe. 0.5 ml of air was then drawn into each syringe. Each of the solutions was incubated at room temperature for approximately five minutes. While the solutions were incubating, two serological pipettes were dipped in a red dyed water solution to withdraw a droplet of water to use as a measuring guide. The red droplets of water were moved to the zero mark of the pipettes by tilting them horizontally. The pipettes were attached to the syringes with a piece of rubber tubing. A ring stand and clothes pins supported the syringes and pipettes so they would stand vertically. A timer was used to record the volume shown on the pipette, which represented the amount of carbon dioxide being
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