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I'm familiar with cellular respiration. Cellular respiration is the set intracellular chemical reactions that utilize oxygen. One example reaction is this:

C6H12O6 + 6O2 -> 6CO2  + 6H20 + heat

Another example reaction is this:

Food + oxygen -> carbon dioxide + water + energy

But there are many chemical reactions in cellular respiration. There are pathways that produce more energy like oxidative phosphorylation. There's glycolysis, the Krebs cycle, and oxidative phosphorylation, and each of these pathways has many chemical reactions.

Why is oxygen so helpful in breaking down food? Why is oxygen so helpful in chemical reactions?

With water, the answer is obvious. Water is a solvent. Water is polar. Water has a polar shape since the two hydrogen atoms are at one side of a tetrahedron and the oxygen's lone valence electrons are at the opposite side of a tetrahedron, which gives water polarity.

What properties of oxygen make oxygen so helpful in cellular respiration? I know that oxygen is an electron acceptor. Are there other properties that make oxygen helpful in cellular respiration?

Is oxidation one of the relevant properties that helps us make energy from food? Is it the oxidation of glucose inside the cytosol at a specific temperature?

When we look at the chemical reaction

C6H12O6 + 6O2 -> 6CO2  + 6H20 + heat

Is that an example of glucose oxidizing inside the cytosol at a warm temperature?

It makes sense that, since fruits and vegetables oxidize at room temperature, small molecules of glucose would oxidize very quickly at warm temperatures inside the cell.

Is oxidation the relevant property of oxygen that helps us get energy from food in cellular respiration?

ktm5124
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    This is a very basic chemical question and has already attracted three close votes. I suggest you read an elementary biochemical text — but not a biology text. In the past I would have recommended Berg et al. on NCBI Bookshelf, but that has been withdrawn. If you have $100 to spare, the 9th edition would be a sound investment in your education. – David Dec 06 '21 at 21:20

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Good question. Why oxygen? Why not something else?

Fortunately the answer is well known and a rudimentary one in biochemistry. I offer a great paper on this by Babcock from 1999 in PNAS. I really recommend you read it all, it's relevant, within the scope of your question and well written in my view.

Excerpt with the answer:

Despite its biochemical versatility, however, >95% of the oxygen that we consume is used in respiration. High-energy electrons derived from food traverse the mitochondrial electron transport chain in a series of exergonic redox reactions. These energetically downhill electron transfers are used to develop the chemisosmotic proton gradient that ultimately produces ATP. Oxygen is the final electron acceptor in this respiratory cascade, and its reduction to water is used as a vehicle by which to clear the mitochondrial chain of low-energy, spent electrons.

The utilization of dioxygen by life is a very efficient strategy and the movement and control of pathways and mechanisms relating to oxygen is highly conserved and tightly controlled.

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