Which process occurs within the mitochondria?

Krebs cycle

Explanation:

The Krebs cycle is a set of chemical events that all aerobic organisms employ to generate energy by converting acetate (which comes from carbs, lipids, and proteins) to carbon dioxide. There are various alternatives to the TCA cycle in theory, but it appears that the TCA cycle is the most efficient.

Mitochondria, using oxygen available within the cell convert chemical energy from food in the cell to energy in a form usable to the host cell. The process is called oxidative phosphorylation and it happens inside mitochondria. ... In heart muscle cells about 40% of the cytoplasmic space is taken up by mitochondria.

Explanation:

The process is called oxidative phosphorylation and it happens inside mitochondria. In the matrix of mitochondria the reactions known as the citric acid or Krebs cycle produce a chemical called NADH. NADH is then used by enzymes embedded in the mitochondrial inner membrane to generate adenosine triphosphate (ATP).

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