PHYSIOLOGY
MUSCLE ENERGETICS GLYCOLYSIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Fructose-2, 6-biphosphate
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Glucose-6-phosphate
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GTP
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ATP
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Detailed explanation-1: -Phosphofructokinase. The key regulatory enzyme of glycolysis is phosphofructokinase. It is inhibited by ATP and citrate and activated by AMP (and ADP), Pi, and fructose 2, 6-bisphosphate.
Detailed explanation-2: -Phosphofructokinase is activated by AMP and fructose-2, 6-bisphosphate and inhibited by ATP, while fructose-1, 6-bisphosphatase is regulated in the opposite manner by the same intermediates. The result is a coordinated control of carbon flux via glycolysis and gluconeogenesis in the liver.
Detailed explanation-3: -Effects on glucose metabolism Fru-2, 6-P2 strongly activates glucose breakdown in glycolysis through allosteric modulation (activation) of phosphofructokinase 1 (PFK-1).
Detailed explanation-4: -Fructose-2, 6-bisphosphate functions as a potent allosteric activator of PFK1, a rate-limiting enzyme of glycolysis. Therefore, TIGAR inhibits glycolysis, thereby redirecting cellular glucose metabolism to the pentose phosphate pathway shunt.