The citric acid cycle, also known as the Krebs cycle or TCA cycle, occurs in the mitochondria of eukaryotic cells. In prokaryotic cells, which lack membrane-bound organelles, the cycle takes place in the cytosol.
The mitochondria, often referred to as the powerhouse of the cell, are where key metabolic processes occur, including the citric acid cycle. Here, acetyl-CoA combines with oxaloacetate to begin the cycle, leading to the production of energy carriers like NADH and FADH2, which are essential for the subsequent electron transport chain that generates ATP.
In summary, the citric acid cycle is crucial for cellular respiration, and its location in the mitochondria is vital for its role in energy production.