Respiration in Plants - Respiratory balance sheet

The respiratory balance sheet is a theoretical calculation of the net gain of $ATP$ for every molecule of glucose oxidized during aerobic respiration.

It is based on certain assumptions: the metabolic pathway is sequential (Glycolysis $\rightarrow$ TCA Cycle $\rightarrow$ ETS), $NADH$ synthesized in glycolysis is transferred into the mitochondria, and no intermediates of the pathway are utilized to synthesize any other compound.

In the Electron Transport System (ETS), the oxidation of one molecule of $NADH$ gives $3$ molecules of $ATP$, and one molecule of $FADH_2$ gives $2$ molecules of $ATP$.

During Glycolysis, there is a net gain of $2$ $ATP$ (Direct) and $2$ $NADH$.

In the Link Reaction (oxidative decarboxylation of Pyruvate), $2$ molecules of $NADH$ are produced per glucose molecule.

In the Krebs Cycle (TCA), per glucose molecule (two turns), there is a gain of $2$ $GTP$ (equivalent to $ATP$), $6$ $NADH$, and $2$ $FADH_2$.

The total theoretical yield of $ATP$ per glucose molecule is $38$ $ATP$, though in most eukaryotic cells, the net gain is $36$ $ATP$ due to the cost of transporting $NADH$ into the mitochondria.