A quick glance reveals that we have taken glucose a small fraction along the way of oxidizing every carbon in it to CO2 and H2O. The complete oxidation happens under aerobic condition when the glycolytic pathway is followed by the Kreb's cycle. Pyruvate formed in glycolysis enters the mitochondrial matrix, and get oxidatively decarboxylated to a 2C molecule, acetylCoA by the enzyme pyruvate dehydrogenase.
Acetyl CoA then enters the Kreb's cycle (also called the tricarboxylic acid (TCA) cycle. It is shown below.