Biochem Module 7 Questions and Answers Already Graded A

Biochem Module 7 Questions and Answers Already Graded A True or False: The Δ G value for a particular reaction is -78kJ/mol. This value indicates the reaction is spontaneous. true True or false: A biochemical metabolic pathway is a single reaction that converts starting material into products. false Three ATP molecules are used in the energy-investing stage of glycolysis. false The citric acid cycle occurs in the presence of oxygen. true The β -oxidation pathway only degrades odd-numbered fatty acids. true In total, how many ATP or NADH are produced (or required) in the glucose to pyruvate steps in glycolysis? - 1 NADH required - 1 ATP and 2 NADH required - 2 ATP and 2 NADH produced - 2 ATP producedNone of the above - 2 ATP and 2 NADH produced In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the fructose-6-phosphate to fructose-1,6-phosphate step in glycolysis? - 1 ATP required - 1 ATP produced - 2 ATP produced - 2 ATP required - None of the above - 1 ATP required What is the primary product of glycolysis? - Glucose - Glucose-6-phosphate - phosphoenolpyruvate - GAP and DHAP - Pyruvate - Pyruvate In glycolysis, when glucose enters a cell, it is immediately phosphorylated to form glucose-6- phosphate. The phosphate donor in this reaction is ATP, and the enzyme is ________. - Hexokinase - Aldolase - CoA - Phosphohexose isomerase - None of the above - Hexokinase In the last reaction of glycolysis, ATP is formed by the direct transfer of a phosphate group from a metabolite to ADP. This process is referred to as: - Substrate-level phosphorylation - Protein phosphorylation - Lipid phosphorylation - Isomerization - Photo-protein dephosphorylation Substrate-level phosphorylation Under anaerobic conditions, to which compound is pyruvate converted? - Ethanol - DHAP - Hexokinase - GAP - None of the above - Ethanol There are ___________ reactions in glycolysis. 6 8 9 10 12 10 The reactions of glycolysis take place in/on the ___________. - Mitochondria - Vacuoles - Ribosome - Cytosol - None of the above - Cytosol How is ATP used in the initial steps of glycolysis? - Lipid phosphorylation reagent - Isomerization reaction - Source for phosphorylation - Protein production - None of the above - Source for phosphorylation Which of the following is a cyclic pathway? CAC PDH Glycolysis Oxidative phosphorylation β -oxidation CAC How many ATP molecules does NADH yield after oxidative phosphorylation? 1.5 2 2.5 3 3.5 2.5 Besides NADH and FADH2, what energy molecule is produced directly in the citric acid cycle? A. CO2 B.ATP C. CTP D. UTP E. None of the above E. None of the above What molecule is missing in the following reaction? A. PDH B. Isocitrate C. Fumarate D. FADH2 E. Succinyl-CoA B. Isocitrate The enzymes and coenzymes of the citric acid cycle are all present in the ________. - Mitochondria - Vacuoles - Nucleus - Lysosomes - None of the above - Mitochondria Cellular respiration is the process of cells taking in ______ and producing ______ to generate energy. A. Glucose; NADH B. FAD; FADH2 C. CO2; ATP D. NAD+; NADH E. O2; CO2 E. O2; CO2 The complete degradation of glucose via cellular respiration occurs in ______ phases. 1 2 3 alternate reversible 3 What are the names of the three enzymes that convert pyruvate to acetyl-CoA A. P, D, and H B. Enzyme A, Enzyme B, and Enzyme C C. Enzyme a, Enzyme b, and Enzyme c D. E1, E2, and E3 E. None of the above D. E1, E2, and E3 Of the following, which coenzyme(s) are necessary for β -oxidation? A. O2 B. FAD C. GTP D. Both A and B E. None of the above B. FAD Which of the following letters corresponds to the α -carbon of a fatty acid? A B C D E B between C and COOH The process for degrading fatty acids is commonly referred to as: A. β -degradation B. α -degradation C. Spiral D. β -spiral E. α -spiral D. β -spiral In one step of the glycolysis pathway, a six-carbon compound is broken into two three-carbon fragments, only one of which can be further degraded in the glycolysis pathway. What happens to the other three-carbon fragment? In step 5 of glycolysis, glucose (six-carbon) is converted to GAP and DHAP (both 3- carbons). GAP goes on in the glycolysis pathway. The other, DHAP, cannot go on through glycolysis directly; it is converted to GAP by triose phosphate isomerase. Glucose contains ___(A)_____ carbon atoms. The oxidation of a glucose molecule utilizes ______(B)______ ATP. Later, the ____(C)_____ three-carbon products of glycolysis produce ____(D)______ ATP by direct phosphorylation, which gives a net yield of two ATP. In addition, ____(E)_____ NADH are produced in glycolysis. Word bank: one, two, three, four, five, six A) six B) two C) two D) four E) two Consider the fatty which has 20 carbons (below). A. (2 pts) How many cycles of β -oxidation are required? Briefly explain. B. (2 pts) How many acetyl-CoA are produced? Briefly explain. C. (1 pts) How many NADH and FADH2 are produced from β -oxidation (only) of this molecule? A. 9 cycles are required for oleic acid. Each cycle removes two carbon units. ON the final cycle, two acetyl groups are produced. B. There are 10 acetyl-CoA groups produced. Two acetyl-CoA groups on the last cycle. C.There are 9 NADH and 9 FADH2 molecules produced. One per cycle. The complete oxidative catabolism of fatty acids to form CO2 and H2O occurs in three phases. Describe the each of the three phases giving the important pathway in each phase and the energy molecules produced in each. Answer: First phase: Fatty acid metabolism begins with b-oxidation which degrades the molecule into acetyl-CoA and also produces 1 FADH2 and 1 NADH molecules per cycle. Second Phase: the acetyl-CoA groups are shuttled through the citric acid cycle to generate GTP, NADH, FADH2 molecules along with the release of CO2. Third Phase: the NADH and FADH2 coenzymes are themselves oxidized in the mitochondria to yield ATP by a process called oxidative phosphorylation.