Answer
From glycolysis the net number of ATPs produced is 2. Actually, 4 ATPs are generated but two are consumed in the phosphorylation of glucose and fructose to form fructose diphosphate. Other metabolites from glycolysis are 2 pyruvates, 2 NADH and 2H2O.
Glycolysis can be either anaerobic or aerobic. If oxygen is present the pyruvates are funneled into the citric acid Krebs/TCA cycle.
Work Step by Step
The citric acid reactions take place in the mitochondria. AcetylCoA generates oxaloacetic acid (OAA) which is converted to citric acid which through several steps is converted to malate. In the citric acid cycle three molecules of NADH and one of FADH2 are formed and 2 ATP s are produced.
The next step after the Citric Acid/Tricarboxylic Acid cycle is the electron transfer chain reactions (ETC). The electron transporters re NAD and NADH. These proteins transfer electrons between substrates and thus facilitate reduction-oxidation reactions that generate energy
The products of the ETC reactions are the following:
NADH generates 25 ATPs
FADH2 generates 3 ATPs
Two ATPs are also generated by glycolysis and 2 in the mitochondrial matrix reactions
Thus the aerobic respiration reactions generate at least 32 ATPs. But this number varies with tissue/cell type and may be as high as 34
Overall reaction for aerobic respiration:
C6H12O6+6O2=6CO2+6H2O+ATP(34-38)
