And once the pyruvate moves into the matrix of the mitochondria, before it begins the citric acid cycle, we have to transform that pyruvate into acetyl coenzyme a. So, ultimately, a two carbon component from the pyruvate is transferred onto a carrier molecule known as coenzyme a, or simply COA. And so once we form the CETL coenzyme A molecule in the pyruvate decorboxylation process, only then can the citric acid cycle actually begin. And so let's focus on step one. In step one, we have a water molecule, this acetyl coenzyme a, as well as an oxyloacetate, react to ultimately produce a six carbon molecule known as citrate. So notice we begin with the oxyloacetate of four carbon molecules, so 1234.