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Questions and Answers
What is the major pathway for glucose metabolism that occurs in the cytosol of all cells?
What is the major pathway for glucose metabolism that occurs in the cytosol of all cells?
Why do erythrocytes rely completely on glucose as their metabolic fuel?
Why do erythrocytes rely completely on glucose as their metabolic fuel?
Which enzyme system is required for glucose oxidation beyond pyruvate?
Which enzyme system is required for glucose oxidation beyond pyruvate?
In which type of cells are elevated levels of GAPDH seen, potentially contributing to increased glycolysis?
In which type of cells are elevated levels of GAPDH seen, potentially contributing to increased glycolysis?
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What is the fate of pyruvate in fast-growing cancer cells?
What is the fate of pyruvate in fast-growing cancer cells?
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What causes lactic acidosis according to the text?
What causes lactic acidosis according to the text?
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Which vitamin deficiency can lead to impaired pyruvate dehydrogenase activity?
Which vitamin deficiency can lead to impaired pyruvate dehydrogenase activity?
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What is the role of hexokinase in glycolysis according to the text?
What is the role of hexokinase in glycolysis according to the text?
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What is the role of calcium ions in insulin secretion?
What is the role of calcium ions in insulin secretion?
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Which enzyme is involved in the conversion of glucose 6-phosphate to fructose 6-phosphate in glycolysis?
Which enzyme is involved in the conversion of glucose 6-phosphate to fructose 6-phosphate in glycolysis?
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What is the significance of the reactions catalyzed by hexokinase, phosphofructokinase, and pyruvate kinase in glycolysis?
What is the significance of the reactions catalyzed by hexokinase, phosphofructokinase, and pyruvate kinase in glycolysis?
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What metabolic consequence does phosphorylation of fructose to fructose 1-phosphate have in glycolysis?
What metabolic consequence does phosphorylation of fructose to fructose 1-phosphate have in glycolysis?
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Why is enolase inhibited by fluoride?
Why is enolase inhibited by fluoride?
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What is the irreversible nature of pyruvate kinase reaction attributed to?
What is the irreversible nature of pyruvate kinase reaction attributed to?
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Why does lactate dehydrogenase catalyze the reduction of pyruvate to lactate under anaerobic conditions?
Why does lactate dehydrogenase catalyze the reduction of pyruvate to lactate under anaerobic conditions?
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What happens to pyruvate under aerobic conditions?
What happens to pyruvate under aerobic conditions?
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What is the role of glucokinase in the liver?
What is the role of glucokinase in the liver?
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How does glucokinase activity affect ATP levels in liver cells?
How does glucokinase activity affect ATP levels in liver cells?
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What is the main function of hexokinase in the liver under normal conditions?
What is the main function of hexokinase in the liver under normal conditions?
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How does the closure of an ATP-potassium channel impact cellular function?
How does the closure of an ATP-potassium channel impact cellular function?
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What is the role of fructose 1-phosphate in glycolysis according to the text?
What is the role of fructose 1-phosphate in glycolysis according to the text?
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Which enzyme catalyzes the conversion of glucose 6-phosphate to fructose 6-phosphate in glycolysis?
Which enzyme catalyzes the conversion of glucose 6-phosphate to fructose 6-phosphate in glycolysis?
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What does the fusion of insulin secretory granules with the cell membrane result in?
What does the fusion of insulin secretory granules with the cell membrane result in?
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Which compound is important at the junction of several metabolic pathways including Glycolysis and glycogenolysis?
Which compound is important at the junction of several metabolic pathways including Glycolysis and glycogenolysis?
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What effect does fluoride have on enolase?
What effect does fluoride have on enolase?
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Why is the reaction catalyzed by pyruvate kinase considered irreversible under physiological conditions?
Why is the reaction catalyzed by pyruvate kinase considered irreversible under physiological conditions?
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What happens to pyruvate under anaerobic conditions?
What happens to pyruvate under anaerobic conditions?
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What is the fate of NADH formed in glycolysis under aerobic conditions?
What is the fate of NADH formed in glycolysis under aerobic conditions?
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What is the main factor that determines whether glycolysis can function aerobically or anaerobically?
What is the main factor that determines whether glycolysis can function aerobically or anaerobically?
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Why do erythrocytes rely completely on glucose as their metabolic fuel?
Why do erythrocytes rely completely on glucose as their metabolic fuel?
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What might be a potential consequence of inhibiting GAPDH in cancer cells?
What might be a potential consequence of inhibiting GAPDH in cancer cells?
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What is the significance of skeletal muscle performing glycolysis in the absence of oxygen?
What is the significance of skeletal muscle performing glycolysis in the absence of oxygen?
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Skeletal muscle can metabolize glucose both aerobically and anaerobically
Skeletal muscle can metabolize glucose both aerobically and anaerobically
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Glucose is metabolized to fructose by the pathway of glycolysis
Glucose is metabolized to fructose by the pathway of glycolysis
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Acetyl-CoA can enter the citric acid cycle for complete oxidation to water and NADPH
Acetyl-CoA can enter the citric acid cycle for complete oxidation to water and NADPH
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Pyruvate is the precursor of fatty acids and cholesterol in the metabolic role of glucose
Pyruvate is the precursor of fatty acids and cholesterol in the metabolic role of glucose
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Glycogen is stored in skeletal muscle as a source of energy for muscle contraction.
Glycogen is stored in skeletal muscle as a source of energy for muscle contraction.
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In gluconeogenesis, substrates such as lactate and pyruvate enter the mitochondrion to yield acetyl-CoA for the synthesis of glucose.
In gluconeogenesis, substrates such as lactate and pyruvate enter the mitochondrion to yield acetyl-CoA for the synthesis of glucose.
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The brain can meet about 50% of its energy needs from ketone bodies during prolonged fasting.
The brain can meet about 50% of its energy needs from ketone bodies during prolonged fasting.
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Most tissues, including the brain, have a substantial requirement for glucose as an energy source.
Most tissues, including the brain, have a substantial requirement for glucose as an energy source.
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Glycolysis can only occur aerobically in cells with mitochondria.
Glycolysis can only occur aerobically in cells with mitochondria.
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Elevated levels of GAPDH in cancer cells lead to a decrease in glycolysis rates.
Elevated levels of GAPDH in cancer cells lead to a decrease in glycolysis rates.
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Methylglyoxal inhibits GAPDH in normal cells but not in cancer cells.
Methylglyoxal inhibits GAPDH in normal cells but not in cancer cells.
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Skeletal muscle can perform glycolysis at very high levels of work output and survive anoxic episodes by utilizing oxygen efficiently.
Skeletal muscle can perform glycolysis at very high levels of work output and survive anoxic episodes by utilizing oxygen efficiently.
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In glycolysis, fructose 1-phosphate bypasses the main regulatory steps of glycolysis.
In glycolysis, fructose 1-phosphate bypasses the main regulatory steps of glycolysis.
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The reaction catalyzed by enolase in glycolysis involves a hydration reaction.
The reaction catalyzed by enolase in glycolysis involves a hydration reaction.
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The reactions catalyzed by hexokinase, phosphofructokinase, and pyruvate kinase in glycolysis are freely reversible.
The reactions catalyzed by hexokinase, phosphofructokinase, and pyruvate kinase in glycolysis are freely reversible.
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Increased lipogenesis in the liver and adipose tissue can be triggered by elevated levels of fructose in the diet.
Increased lipogenesis in the liver and adipose tissue can be triggered by elevated levels of fructose in the diet.
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What is the role of glucokinase in the liver, specifically?
What is the role of glucokinase in the liver, specifically?
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How is glucokinase activity linked to insulin secretion?
How is glucokinase activity linked to insulin secretion?
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What is the end product of glycolysis when it occurs anaerobically?
What is the end product of glycolysis when it occurs anaerobically?
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What is one of the major functions of hexokinase in liver cells?
What is one of the major functions of hexokinase in liver cells?
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In what way does glucokinase contribute to lipogenesis?
In what way does glucokinase contribute to lipogenesis?
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Which process utilizes glucose to provide reducing equivalents (NADPH) for fatty acid synthesis?
Which process utilizes glucose to provide reducing equivalents (NADPH) for fatty acid synthesis?
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What is the main metabolic role of acetyl-CoA in glucose metabolism?
What is the main metabolic role of acetyl-CoA in glucose metabolism?
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Which component of skeletal muscle metabolism can occur in the absence of oxygen?
Which component of skeletal muscle metabolism can occur in the absence of oxygen?
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Which enzyme is responsible for converting fructose to fructose 1-phosphate in glycolysis?
Which enzyme is responsible for converting fructose to fructose 1-phosphate in glycolysis?
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What is the main site of regulation in glycolysis that involves irreversible reactions?
What is the main site of regulation in glycolysis that involves irreversible reactions?
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How does the phosphorylation of fructose to fructose 1-phosphate affect glycolysis?
How does the phosphorylation of fructose to fructose 1-phosphate affect glycolysis?
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Which compound plays a critical role at the intersection of several metabolic pathways including glycolysis, glycogenesis, and glycogenolysis?
Which compound plays a critical role at the intersection of several metabolic pathways including glycolysis, glycogenesis, and glycogenolysis?
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Why is the reaction catalyzed by enolase considered crucial in glycolysis?
Why is the reaction catalyzed by enolase considered crucial in glycolysis?
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What is the main reason for the irreversible nature of pyruvate kinase reaction under physiological conditions?
What is the main reason for the irreversible nature of pyruvate kinase reaction under physiological conditions?
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Why is NADH reduced to lactate under anaerobic conditions and not reoxidized through the respiratory chain?
Why is NADH reduced to lactate under anaerobic conditions and not reoxidized through the respiratory chain?
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What is the fate of pyruvate under aerobic conditions in liver glycolysis?
What is the fate of pyruvate under aerobic conditions in liver glycolysis?
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