Question

Which of the following statements regarding catabolic pathways are true? 1. When proteins are used as a source of energy for the body, the proteins are first broken down to produce amino acids, which are then converted into either glyceraldehyde 3 phosphate or acety CoA The enzyme phosphofructokinase is subject to allostericinhibition by high levels of citric acid When acety CoA builds up in the call it increases the activity of the enzyme that synthesizes oxalacetato from pyruvate and carbon dioxide. Acety CoA is acting as an) allostoric activator B-oxidation is a process that breaks the B-glycosidic inkages in glycogen V. The immediate energy source tht drives ATP synthesis by ATP synthase during cridative phosphorylation is the concentration gradient across the membrane holding the ATP synthase

Answer 1

Answer: Catabolic pathways are metabolic pathways that involves break down of large molecules in to small molecules. These small molecules undergo oxidation to release energy that is used in synthesizing macromolecules (Anabolic reactions). In the body, proteins break down in to amino acids that are used to produce glyceraldehyde-3-phosphate and acetyl-CoA. These two molecules later produce energy by oxidation. This is an example of catabolic reaction because proteins are catabolized to produce energy. Hence, option I is the correct answer. The statement " phosphofructokinase subjected to allosteric inhibition by high levels of citric acid is not a catabolic reaction because there is no breakdown of molecules in the inhibition process. Hence, option II is incorrect. The statement Acetyl build up in the cell and increases the activity of the enzymes that synthesizes oxaloacetate from pyruvate and carbon dioxide is an example of anabolic reaction. Hence, option III is incorrect. Beta-oxidation is process that breaks fats but not glycogen. Hence, option IV is incorrect. ATP synthesis from ATP synthase is an anabolic reaction but not catabolic reaction. Hence, option V is incorrect.