Here's why:
* Pyruvate dehydrogenase complex (PDC): The enzyme complex responsible for this oxidation uses NAD+ as an electron acceptor. NAD+ is reduced to NADH in the process.
* Oxygen's role: Oxygen is needed later in the electron transport chain (ETC) to act as the final electron acceptor, allowing for the regeneration of NAD+ and the production of ATP.
In summary:
* The oxidation of pyruvate to acetyl-CoA happens in the mitochondrial matrix.
* It's part of the link reaction connecting glycolysis to the Krebs cycle.
* It doesn't directly need oxygen but is a precursor to processes that do.
Let me know if you'd like more detail about any of these steps!
