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The following statements (I-V) are either true or false characteristics and functions of the important protein lactate dehydrogenase (LDH). I. Plasma total LDH level is elevated in hemolysis. II. The two subunits LDH-H and LDH-M are encoded by the LDHA and LDHB genes, respectively. III. High levels of LDH in cerebrospinal fluid are often associated with bacterial meningitis. IV. Mutations in the LDHA gene and resulting deficiencies in LDH-H activity can result in Glycogen Storage Disease XI. V. LDH enzymes are most commonly specific for L-lactate and these L-LDH enzymes have the EC number 1.1.1.27. D-LDH enzymes have the EC number 1.1.1.28. Which of the following options (A-E) is/are CORRECT? A. Statements I, III, and V are true; Statements II, IV, and V are false. B. Statements II and IV are false. C. All statements are false. D. All statements are true. Arsenate is a toxic ion that can interfere with both glycolysis and oxidative phosphorylation. Arsenate resembles inorganic phosphate (P) and can replace it in many enzymatic reactions. One such reaction is catalyzed by glyceraldehyde 3-phosphate dehydrogenase in glycolysis. Arsenate competes with phosphate for entry into the active site of glyceraldehyde 3-phosphate dehydrogenase and upon completion of the reaction, instead of the normal product, 1,3-bisphosphoglycerate, the mixed anhydride 1-arsenato 3-phosphoglycerate is formed. This undergoes rapid spontaneous hydrolysis into arsenate plus 3-phosphoglycerate, the latter being a normal intermediate in glycolysis. Glycolysis is able to proceed from the step at 3-phosphoglycerate. What would be the effect of arsenate in glycolysis? (a) Arsenate activates glycolysis so that more ATP and NADH are generated for every glucose molecule. (b) In the presence of arsenate, there is no net formation of ATP from glycolysis, but NADH generation is not directly affected. (c) Arsenate brings glycolysis to an abrupt stop with immediate lethal consequences. (d) In the presence of arsenate, glycolysis produces fewer ATP and NADH molecules per glucose molecule. (e) Arsenate does not affect the number of ATP or NADH molecules generated per glucose molecule.

The following statements (I-V) are either true or false characteristics and functions of the important protein lactate dehydrogenase (LDH).
I. Plasma total LDH level is elevated in hemolysis. II. The two subunits LDH-H and LDH-M are encoded by the LDHA and LDHB genes, respectively. III. High levels of LDH in cerebrospinal fluid are often associated with bacterial meningitis. IV. Mutations in the LDHA gene and resulting deficiencies in LDH-H activity can result in Glycogen Storage Disease XI. V. LDH enzymes are most commonly specific for L-lactate and these L-LDH enzymes have the EC number 1.1.1.27. D-LDH enzymes have the EC number 1.1.1.28.
Which of the following options (A-E) is/are CORRECT?
A. Statements I, III, and V are true; Statements II, IV, and V are false. B. Statements II and IV are false. C. All statements are false. D. All statements are true.

Arsenate is a toxic ion that can interfere with both glycolysis and oxidative phosphorylation. Arsenate resembles inorganic phosphate (P) and can replace it in many enzymatic reactions. One such reaction is catalyzed by glyceraldehyde 3-phosphate dehydrogenase in glycolysis. Arsenate competes with phosphate for entry into the active site of glyceraldehyde 3-phosphate dehydrogenase and upon completion of the reaction, instead of the normal product, 1,3-bisphosphoglycerate, the mixed anhydride 1-arsenato 3-phosphoglycerate is formed. This undergoes rapid spontaneous hydrolysis into arsenate plus 3-phosphoglycerate, the latter being a normal intermediate in glycolysis. Glycolysis is able to proceed from the step at 3-phosphoglycerate. What would be the effect of arsenate in glycolysis?
(a) Arsenate activates glycolysis so that more ATP and NADH are generated for every glucose molecule. (b) In the presence of arsenate, there is no net formation of ATP from glycolysis, but NADH generation is not directly affected. (c) Arsenate brings glycolysis to an abrupt stop with immediate lethal consequences. (d) In the presence of arsenate, glycolysis produces fewer ATP and NADH molecules per glucose molecule. (e) Arsenate does not affect the number of ATP or NADH molecules generated per glucose molecule.

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