The Krebs cycle, also known as the citric acid cycle or TCA cycle, takes place in the mitochondrial matrix of eukaryotic cells. The mitochondrial matrix is the dense fluid inside the inner membrane of the mitochondrion, containing water, enzymes, coenzymes, and phosphates necessary for the cycle's biochemical reactions
. In prokaryotic cells, which lack mitochondria, the Krebs cycle occurs in the cytosol instead
. Thus, in typical animal and plant cells, the Krebs cycle occurs in the mitochondria, specifically in the matrix region.
