Cellular Respiration In Yeast

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Cellular respiration is a process that takes place in the mitochondria where a chain of metabolic reactions occur in order to generate chemical energy from nutrients such as carbohydrates. The key reactants of this process include oxygen and glucose which yield carbon dioxide and water. Photosynthesis is the process where light energy is converted into chemical energy. The key reactants in photosynthesis are water, light and carbon dioxide which yield glucose and oxygen. In this lab, several different carbohydrate solutions were administered to yeast, and the rate of photosynthesis was measured by the amount of carbon dioxide produced from the reaction of various carbohydrates. The different types of carbohydrates that were used in this study …show more content…
It consists of several major pathways including glycolysis, pyruvate oxidation, the citric acid cycle and finally the electron chain transport. Glycolysis is a multi-step pathway that occurs in the cytoplasm of the cell where one glucose molecule is broken down into two pyruvate molecules. Glycolysis produces 4 ATP’s and 2 NADH. It uses 2 ATP’s in the process for a net of 2 ATP and 2 NADH. This process does not require oxygen. Next the two pyruvate molecules become oxidized into acetyl CoA. The Acetyl CoA reacts with oxaloacetate to start the Krebs cycle. The Krebs cycle takes place in the mitochondrial matrix. During this cycle, 2 ATP, 8 NADH, and 2 FADH2 per glucose are produced. Ultimately electrons are removed from NADH in the electron chain and moved to oxygen to yield H2O, a movement of high energy to low energy to produce the proton gradient. The proton gradient powers ATP production. About 32 ATP are made from the products of 1 molecule of glucose. Fermentation is an anaerobic process where energy can be released from glucose, without the presence of oxygen. During fermentation, organic substances are oxidized in an anaerobic environment without the utilization of an electron chain and oxidative phosphorylation. It is an extension of glycolysis that yields a continuous amount of ATP NAD+ must be present to accept electrons during this oxidation step of glycolysis. There are two forms of …show more content…
During the first phase called carbon fixation, carbon dioxide (Co2) is fixed from an inorganic molecule to an organic molecule (3-PGA) by the enzyme called RuBisCo. The second phase called reduction, is where ATP and NADH help reduce 3-PGA into G3P and ATP and NADPH are then converted to ADP and NADP+. In the final phase called regeneration, the final molecule, RuBp, is regenerated to help the cycle prepare for more Co2 and so the Calvin cycle can continue. The hypothesis for this experiment focuses on a form of enzyme regulation called induction by determining the different rates of respiration by a yeast culture when subjected to different solutions of carbohydrates. The rate of respiration can be measured by the rate of carbon dioxide produced. For the objective of the second part of this study supports the fact that the rate of photosynthesis is dependent on the wavelength (color) of light absorbed. The rate of photosynthesis can be measured by the amount of oxygen produced from various wavelengths of light in the color

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