What reaction(s) of the citric acid cycle involve the addition of H20 as OH¨ to the substrate? (Choose all that apply) O conversion of succinyl-CoA to succinate O conversion of succinate to fumarate conversion of isocitrate to alpha-ketoglutarate synthesis of citrate from oxaloacetate and acetyl CoA O conversion of alpha-ketoglutarate to succinyl-CoA O conversion of citrate to isocitrate conversion of malate to oxaloacetate

9. The equation below depicts the first step of the citric acid cycle. H0 CoA-SH CH-C + 0=C-CO0 HO C-COO citrate s-COA ČH2-COO synthase ČH2 -CO0 Citrate Acetyl-CoA Oxaloacetate AG" = -32.2 kJ/mol a) Explain the chemical conversions that take place during this step. b) Why is this reaction energetically favorable? Explain.

In 1937, two German biochemists published a paper proposing these reactions as part of glucose oxidation: citrate → isocitrate → α-ketoglutarate →succinate → fumarate → malate → oxaloacetate. Adding succinate, fumarate, or malate to thin slices of tissue increased oxygen consumption, supporting the hypothesis that these molecules are intermediates in the process. However, they were puzzled by the observation that these intermediates were still present in the reaction mixture at the end of the experiment. They had thought that intermediates would be consumed as they were converted to the next molecule in the pathway. What explains the observation that these intermediates were still present? a) The pathway is a cycle, constantly regenerating intermediates as glucose is broken down. b) Succinate, fumarate, and malate are not reactants but catalysts, and catalysts are not consumed in the process. c) Succinate, fumarate, and malate increase metabolism and therefore oxygen consumption,…

What four allosteric enzymes or enzyme complexes are responsible for the regulation of the citric acid cycle? Select all that apply. Malate dehydrogenase Fumarase Succinyl CoA synthetase Aconitase a-ketogluatarate dehydrogenase Succinate dehydrogenase Pyruvate dehydrogenase Citrate synthase Isocitrate dehydrogenase

What is the fate of the radioactive label when each of the following compounds is added to a cell extract containing the enzymes and cofactors of the citric acid cycle and the pyruvate dehydrogenase complex?  P.S. A detailed steps explaination would be greatly appreciated. Also, any tips on how to solve such problems if possible? Is there any particular fate that C atoms of the R group for example, have, at the end of the cycle? I usually think of drawing out each step and solving but I believe that there must be a shorter, smarter way to do it and similar questions. Thank you!

alpha-ketoglutarate dehydrogenase will do which of the following: Select one: a. Pyruvate is decarboxylated to become acetyl-CoA producing NADH and Carbon dioxide b. Succinate is oxidized to become fumarate forming FADH2 c. Succinyl-CoA becomes Succinate and forms one ATP molecule and Coenzyme A-SH d. Oxaloacetate combines with the acetyl from acetyl-CoA to produce Citric acid(citrate) e. Malate is oxidized to become oxaloacetate forming NADH f. Isocitrate and then decarboxylated and oxidized to produce alpha-ketoglutarate, Carbon dioxide and NADH g. Citrate is rearranged to become Isocitrate h. Fumarate is combined with water to become Malate i. alpha-ketoglutarate is oxidized and decarboxylated to produce Succinyl-CoA, Carbon dioxide and NADH