How many molecules of glucose is needed to undergo cell respiration?

One molecule of glucose is needed to produce approximately 38 molecules of ATP in each round of aerobic respiration.

Explanation:

In respiration, organisms use food, or glucose made in photosynthesis to obtain energy. Photosynthesizing organisms use light to synthesize chemical energy.

Mitochondria in some organisms provide the most favorable environment for energy metabolism, glucose undergoes a form of combustion, this results in carbon dioxide and water production, together with energy as ATP or adenosine triphosphate.  

   glucose+ oxygen                      →  carbon dioxide+ water+ energy

Thus, only one molecule of glucose is needed to produce approximately 38 molecules of ATP.

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