Here's why:

* Mitochondria are the powerhouses of the cell: They are responsible for generating ATP (adenosine triphosphate), the primary energy currency of the cell.

* Aerobic respiration requires oxygen: Mitochondria contain the necessary enzymes and components for the complete breakdown of glucose in the presence of oxygen.

* Krebs cycle and electron transport chain: These key stages of aerobic respiration occur within the mitochondria.

While glycolysis, the first stage of cellular respiration, happens in the cytoplasm, the remaining steps that require oxygen take place in the mitochondria.