Cellular respiration is the process by which cells consume glucose and oxygen, and break it down into carbon dioxide and water. The process also generates ATP or adenosine triphosphate molecules. These are energy molecules and provide energy for various cellular operations (or functions). Chemically, the process can be written as:
`C_6H_12O_6 + 6O_2 -> 6 CO_2 + 6H_2O + ATP`
The main purpose of this process is to produce energy for maintaining life and other cellular functions. The carbon dioxide produced during the process helps in the greenhouse effect and keeps the planet warm enough for life.
Cellular respiration is complementary to the process of photosynthesis (by which green plants produce glucose molecules and oxygen). Photosynthesis is the process of food production and cellular respiration is the process of food breakdown. Both the processes are necessary for sustenance and propagation of life.
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