Aerobic respiration

Glucose + Oxygen -> Carbon Dioxide + Water + Energy(Word Equation)

C6H12O6 + 6O2 -> 6CO2+ 6H2O+ ATP

As with all forms of cellular respiration , aerobic respiration begins with glycolysis , a metabolic pathway(a series of chemical reactions) that converts glucose (C6H12O6) into pyruvate(CH3COO− + H+).It is divided into 2 phases.

Glycolysis Phase 1

Glucose(C6H12O6) is broken down into 2 PGAL's(C₃H₇O₆P or G6P) , this reaction consumes 2 ATP and involves 2 enzymes , hexokinase and glucokinase. Hence , this phase is also known as the "preparatory" phase.

Glycolysis Phase 2

The 2 PGAL's are then converted to pyruvate(CH3COO− + H+) with the production of 4 equivalents of ATP and 2 equivalents of NADH. This process involves enzymes such as pyruvate kinase and enolase.As 2 ATPs are used in phase 1 , and 4 ATPs are gained in phase 2 , there is a net gain of 2 ATPs in the process of glycolysis.Hence , this face is also known as the "pay-off" phase.

Krebs Cycle

Following glycolysis , if oxygen is present(Oxygen is present during aerobic respiration , not present during anaerobic respiration) , it leads to the Krebs cycle or the citric acid cycle. The Krebs cycle produce carbon dioxide and ATP and takes place within the mitochondrion.One GTP (guanosine triphosphate) is produced which eventually donates a phosphate group to ADP to form one ATP; three molecules of NAD and one of FAD is reduced. the production of the reduced NAD and FAD are far more significant in the cell's energy-generating process. This is because NADH and FADH₂ donate their electrons to an electron transport chain that generates large amounts of energy by forming many molecules of ATP.