MUSCLE PHYSIOLOGY

Detailed explanation-1: -This reaction occurs with the help of the enzyme phosphoglucose isomerase (PI). As the name of the enzyme suggests, this reaction involves an isomerization reaction. Glucose and fructose are isomers.

Detailed explanation-2: -Glucose-6-phosphate will be used in glycogen synthesis (a storage form of glucose), production of other carbon compounds by the pentose-phosphate pathway, or degraded in order to produce energy-glycolysis. In order to be used for energy production, glucose-6-phosphate must first be isomerized in fructose-6-phosphate.

Detailed explanation-3: -Glucose-6-phosphate is isomerized by phosphoglucose isomerase to form fructose-6-phosphate. Fructose-6-phosphate is phosphorylated by phosphofructokinase to form fructose-1, 6-bisphosphate.

Detailed explanation-4: -Glycolysis and Pyruvate Oxidation This is an irreversible step. Phosphoglucose isomerase. Glucose 6-phosphate (G6P) is converted to its isomer, fructose 6-phosphate (F6P).

Detailed explanation-5: -Glucose-6-phosphate (G6P) is changed into fructose-6-phosphate (F6P) by phosphoglucoisomerase (phosphoglucose isomerase) in the second step. This reaction also requires Mg2+. F6P can enter the glycolytic pathway from the next point. This reaction has a low free energy charge.