* ATP (adenosine triphosphate): This is the primary energy currency of cells.

* Water (H₂O): Water is formed as a byproduct of the electron transport chain.

* Carbon dioxide (CO₂): Carbon dioxide is released as a waste product, primarily during the Krebs cycle.

In summary:

Cellular respiration takes in glucose and oxygen, and produces ATP, water, and carbon dioxide. This process is essential for life as it provides the energy needed for all cellular processes.