Glycolysis takes place in the cytoplasm. Within the mitochondrion, the citric acid cycle occurs in the mitochondrial matrix, and oxidative metabolism occurs at the internal folded mitochondrial ...

A second autotrophic pathway (Arnon–Buchanan cycle) uses a reductive citric acid cycle and is found in anaerobic or microaerophilic bacteria and archaea. A third autotrophic pathway (Wood ...

But it's not just sour citrus fruits that have citric acid. All plants and animals have small traces of it. One reason is that it's an important intermediate in metabolism, which is the pathway ...