MUSCLE PHYSIOLOGY

Detailed explanation-1: -In order for pyruvate from glycolysis to enter the Kreb’s Cycle it must first be converted into acetyl-CoA by the pyruvate dehydrogenase complex which is an oxidative process wherein NADH and CO2 are formed. Another source of acetyl-CoA is beta oxidation of fatty acids.

Detailed explanation-2: -The Krebs cycle itself actually begins when acetyl-CoA combines with a four-carbon molecule called OAA (oxaloacetate) (see Figure above). This produces citric acid, which has six carbonatoms. This is why the Krebs cycle is also called the citric acid cycle.

Detailed explanation-3: -Within the mitochondria, each pyruvate is broken apart and combined with a coenzyme known as CoA to form a 2-carbon molecule, acetyl-CoA, which can enter the Krebs Cycle. A single atom of carbon (per pyruvate) is “lost” as carbon dioxide. The energy released in this breakdown is captured in two NADH molecules.

Detailed explanation-4: -Glycolysis, Pyruvate Oxidation and the Krebs Cycle Glycolysis, the process of splitting a six-carbon glucose molecule into two three-carbon pyruvate molecules, is linked to the Krebs cycle. For each glucose molecule respired, the cycle reactions occur twice as two pyruvic acid molecules are formed.

Detailed explanation-5: -Two molecules of pyruvate are converted into two molecules of acetyl CoAstart text, C, o, A, end text. Two carbons are released as carbon dioxide-out of the six originally present in glucose.