Respiration:
Respiration is a very important and well-regulated physiological process by which complex organic food is broken down to simpler substances with the liberation of heat energy at a much slower rate.
Combustion:
Combustion is a physio-chemical process that occurs outside the cell involving an uncontrolled process by which huge amounts of heat and light are liberated.
Respiration vs Combustion:
| Respiration | Combustion |
| 1. Respiration is a physiological process | 1. Combustion is a physio-chemical process |
| 2. It occurs within the living cells | 2. It occurs outside the living cells |
| 3. This process can occur in presence or in absence of molecular oxygen | 3. This process can't occur in absence of molecular oxygen |
| 4. It takes place slowly with the help of certain enzymes. | 4. It takes place vigorously without the involvement of enzymes |
| 5. ATP is produced in this process | 5. ATP is not generated in this process |
| 6. This process doesn't damage the cell, only the respiratory substrate is oxidized | 6. The combustible substance is completed destroyed |
| 7. The release of heat energy takes place at a much slower rate | 7. Release of large amount of heat and light takes place quickly. |