PHYSIOLOGY
MUSCLE ENERGETICS GLYCOLYSIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Glycolysis
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Krebs Cycle
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HMP Shunt
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ETC
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Detailed explanation-1: -PFK1 is allosterically inhibited by high levels of ATP but AMP reverses the inhibitory action of ATP. Therefore, the activity of the enzyme increases when the cellular ATP/AMP ratio is lowered. Glycolysis is thus stimulated when energy charge falls.
Detailed explanation-2: -Explanation: When there are high levels of ATP in the blood, ATP itself can act as a signal for the inhibition of ATP production. phosphofructokinase-1 (PFK-1) and pyruvate kinase are major sites of glycolytic regulation. ATP can inhibit these enzymes by binding to their allosteric sites.
Detailed explanation-3: -The enzymes involved in the generation of ATP are glyceraldehyde-3-phosphate dehydrogenase (G3PD) and phosphoglycerate kinase (PGK).
Detailed explanation-4: -rise in AMP increases metabolism through pathways to restore energy (i.e. glycolysis, citric acid cycle etc.). Hexokinase: Catalyzes the phosphorylation of hexoses in general and is found in all cells that metabolize glucose.
Detailed explanation-5: -Insulin activates glucokinase, PFK1, and pyruvate kinase, the three important enzymes catalyzing the irreversible steps in glycolysis in order to process the available substrate.