Fig. 2. Schematic representation of carbon incorporation from glucose into acetyl-CoA, the precursor for fatty acid biosynthesis.

Carbon atom numbering for metabolites (pyruvate, PYR; acetyl-CoA, AcCoA) is ordered from left to right, while numbers indicate the C position in the original glucose molecule. ED indicates Entner-Doudoroff pathway, EMP is Embden-Meyerhof-Parnas glycolysis, and PP is pentose phosphate pathway. Gray background shading indicates those C positions released by pyruvate dehydrogenase as CO₂.