Aerobic And Yeast Lab Report
ANAEROBIC AND AEROBIC METABOLISM
Lab 5
BCEM 341 – Winter 2014
Nebojsa Kuljic
10066717
Partner: Kendra Skalyn
B02
Introduction Cells of all organisms can obtain energy through the combustion of sugars, either in the presence of oxygen (Aerobically) or without oxygen (Anaerobically). The purpose of this experiment was to perform a quantitative investigation of the differences between Anaerobic and Aerobic metabolism using pea seedlings and yeast organisms [1]. Aerobically, sugars such as glucose are transformed into pyruvate [2] and then into Acetyl CoA. This is then put through the citric acid cycle which is a series of reactions that oxidize acetyl units into carbon dioxide [2]. Following …show more content…
This was done by measuring the changes in volumes of gas surrounding the organisms with a Volumeter. For the experiment with the pea seedlings, the rate of O2 consumption (measured in the presence of CO2 capturing Ascarite) was determined to be 2.6ml over the course of 30 minutes. Using the weight lost by the pea seedlings (assuming all weight loss was due to the metabolism of glucose), and the equation for glucose metabolism, it was theoretically determined that the seedling should have consumed 43.3ml over 30 minutes. This is considerably more than what was measured, but can potentially be explained by the pea seedling undergoing photosynthesis throughout the experiment. By producing O2 as it consumed O2, a lower net change in gas volume could have resulted and then have been mistakenly interpreted as lower oxygen …show more content…
In order to confirm the suspicion that this gas was CO2, a side experiment was done which funneled the gas into a tube filled with BaOH. Providing it was CO2, the BaOH should have reacted to produce a precipitate, which according to observations, was the case. Repeating the Volumeter experiment, this time with yeast/glucose and yeast/water solutions, comparing them to a control, the rate of CO2 production was tremendously larger in the yeast/glucose trial than the yeast/water (31.29ml/30min and 0.15ml/30min, respectively). Since the yeast is an organism which carries around internal energy stores, it is capable of metabolism when it has nothing but itself, similarly to the way a human burns its own energy stores (ie: Fat) during fasting. In the presence of an external energy source however, the yeast is able to metabolize everything in sight much more easily, producing much higher volumes of CO2, the same way we handle a full stomach after a big buffet. Based on the volume of CO2 produced with the yeast in just water, the amount of intracellular glucose can be calculated with the same logic of calculated exogenous glucose usage. Intracellular glucose consumed, based on experimental results would therefore be 2.23 x 10-6
Lab 5
BCEM 341 – Winter 2014
Nebojsa Kuljic
10066717
Partner: Kendra Skalyn
B02
Introduction Cells of all organisms can obtain energy through the combustion of sugars, either in the presence of oxygen (Aerobically) or without oxygen (Anaerobically). The purpose of this experiment was to perform a quantitative investigation of the differences between Anaerobic and Aerobic metabolism using pea seedlings and yeast organisms [1]. Aerobically, sugars such as glucose are transformed into pyruvate [2] and then into Acetyl CoA. This is then put through the citric acid cycle which is a series of reactions that oxidize acetyl units into carbon dioxide [2]. Following …show more content…
This was done by measuring the changes in volumes of gas surrounding the organisms with a Volumeter. For the experiment with the pea seedlings, the rate of O2 consumption (measured in the presence of CO2 capturing Ascarite) was determined to be 2.6ml over the course of 30 minutes. Using the weight lost by the pea seedlings (assuming all weight loss was due to the metabolism of glucose), and the equation for glucose metabolism, it was theoretically determined that the seedling should have consumed 43.3ml over 30 minutes. This is considerably more than what was measured, but can potentially be explained by the pea seedling undergoing photosynthesis throughout the experiment. By producing O2 as it consumed O2, a lower net change in gas volume could have resulted and then have been mistakenly interpreted as lower oxygen …show more content…
In order to confirm the suspicion that this gas was CO2, a side experiment was done which funneled the gas into a tube filled with BaOH. Providing it was CO2, the BaOH should have reacted to produce a precipitate, which according to observations, was the case. Repeating the Volumeter experiment, this time with yeast/glucose and yeast/water solutions, comparing them to a control, the rate of CO2 production was tremendously larger in the yeast/glucose trial than the yeast/water (31.29ml/30min and 0.15ml/30min, respectively). Since the yeast is an organism which carries around internal energy stores, it is capable of metabolism when it has nothing but itself, similarly to the way a human burns its own energy stores (ie: Fat) during fasting. In the presence of an external energy source however, the yeast is able to metabolize everything in sight much more easily, producing much higher volumes of CO2, the same way we handle a full stomach after a big buffet. Based on the volume of CO2 produced with the yeast in just water, the amount of intracellular glucose can be calculated with the same logic of calculated exogenous glucose usage. Intracellular glucose consumed, based on experimental results would therefore be 2.23 x 10-6