Question

1. The breakdown of fatty acids can generate a large amount of Acetyl-CoA. In light of this and of the factors that regulate the TCA cycle, what would be the effect of fatty acid breakdown on pyruvate dehydrogenase AND on glycolysis and why is this effect advantageous to the cell when fatty acids are being broken down?

Fatty acid breakdown

2. For the following statement, decide whether the statement is true or false and provide a justification for your answer: The membrane potential (voltage gradient) generated by the electron transport chain results from the movement of electrons from the matrix and into the intermembrane space.

EXTRA CREDIT: None of the reactions of the citric acid cycle (TCA cycle) use molecular oxygen (O2), yet the cycle cannot happen in the absence of oxygen. The reason for this is that the TCA cycle cannot function unless the electron transport chain (ETC) is also functioning, and the ETC requires oxygen as the final electron acceptor. This dependence of the TCA cycle on the ETC is related to the electron carriers that are reduced during the TCA. Given this information, why do you suppose is the biochemical reason of the dependence of the TCA cycle on the ETC? Hint: this reason is similar to the reason why fermentation is needed to allow glycolysis to continue in the absence of oxygen.

Answer 1

Fatty acid Breakdown -when fatty acids forms acetyl coA on oxidation as a product ,it is known as fatty acid breakdown.Acetyl coA is essential for TCA or citric acid cycle as it is starting component or product for this cycle.

TCA cycle -Tricarboxylic acid cycle,also known as citric acid cycle or kreb cycle.

In this cycle or process,acetyl coA is converted into ATP (adenine triphosphate) and carbon dioxide (CO2).

Factors regulating the TCA cycle are enzyme inhibition,product inhibition and considering these factors effect is as follows.

Effect of fatty acid breakdown on pyruvate dehydrogenase or glycolysis-

Glycolysis is a process in which glucose is coneverted into Pyruvate. Pyruvate dehydrogenase is an enzyme that converts pyruvate into acetyl coA by oxidising the pyruvate. This reaction refer to as pyruvate dehydrogenase reaction.Due to fatty acid breakdown,acetyl coA will be formed and this acetyl coA converts into coA .Higher concentration of ratio of acetyl coA to coA inhibit the pyruvate dehydrogenase reaction.

In the cell,mitochondria is the power house of the cell because most of the reaction is carried out in mitochondria.In mitochondria, fatty acid breakdown takes place. Fatty acids are converted into acetyl coA with the release of energy in the form of ATP. Energy source is necessary for respiration of cell,their growth and development.Hence,fatty acid breakdown play an important role in cell development and is advantageous.