The number of ATP molecules formed by substrate level phosphorylation in glycolysis and krebs cycle during complete aerobic oxidation of one molecule of glucose is

In glycolysis, 2(1,3-bisphoglyceric acid → 3-phosphoglyceric acid) and 2(Phosphoenol pyruvate → Pyruvate) produces 2 ATP each. Therefore, total number of ATP produced by substrate level phosphorylation is 4 ATP.In Krebs cycleSuccinyl CoA→ Succinic acid. Then ATP or GTP is produced. Krebs cycle occurs twice for 1 glucose molecule. Therefore, 2ATPs are produced.