ATP is a source of energy required by cells to undergo and perform daily functions. These molecules are produced through the catabolism of carbohydrates, fats and proteins. Sources of ATP can be generated under aerobic respiration and anaerobic respiration, in the presence of oxygen and presence of no oxygen, respectively. Fermentation occurs as well, without oxygen.Fermentation and anaerobic respiration are not the same type of metabolism; they both use a different terminal electron acceptor and produce different products. (Campbell and Reece)
Under aerobic conditions, the catabolism of glucose begins with glycolysis to convert sugar into pyruvate. During pyruvate synthesis into Acetyl CoA, molecules of ATP are produced. Acetyl CoA is then transferred to the mitochondria where the Krebs cycle takes place. The Krebs cycle further produces ATP with the addition of CO2 as the by-product.
Yeast cells are facultative organisms that can use aerobic respiration and fermentation. But in this experiment, yeast cells are in the presence of oxygen performing sugar metabolism, which we measure by the amount of CO2 production. The objective of this experiment is to determine the concentrations of ethanol that have a toxic effect on the amount of CO2 produced under aerobic conditions. We expect to find that as doses of ethanol concentration increases, the production of CO2 will decrease in Saccharomyces cerevisiae. We hope to see results similar to our hypothesis, since it is known that ethanol is toxic to yeast cells. The importance of this study is to gain valuable information on the performance of the organism, whether an inhibitor or non-inhibitor is used to measure its activity.
Materials and Methods
After labelling 7 test tubes with concentrations in percentage and a control tube, we added a constant volume of glucose to each test tube with the addition of different volumes of water and different volumes of ethanol. (T…