During prolonged fasting, which enzyme is activated to promote gluconeogenesis from substrates like lactate or amino acids?
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Correct answer: Phosphoenolpyruvate carboxykinase (PEPCK)
PEPCK catalyzes a key step in gluconeogenesis, converting oxaloacetate to phosphoenolpyruvate, and is induced during fasting or glucagon stimulation to increase hepatic glucose production.
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