NADH bypasses the first phosphorylation site and hence only two ATP molecules are produced per external NADH oxidised through mitochondrial electron transport chain. However, in those animal tissues in which malate shuttle mechanism is present, the oxidation of external NADH will yield almost ATP molecules. Complete oxidation of a glucose molecule in aerobic respiration results in the net gain of ATP molecules in plants as shown in table . .
Since huge amount of energy is generated in mitochondria in the form of ATP molecules they are called ‘power house of the cell’. In the case of aerobic prokaryotes due to lack of mitochondria each molecule of glucose produces ATP molecules. Abnormal rise in respiratory rate of ripening in fruits is called Climacteric . Examples are apple, banana, mango, papaya, pear.
Recent view When the cost of transport of ATPs from matrix into the cytosol is considered, the number will be . ATPs for each NADH H and . ATPs for each FADH oxidised during electron transport system. Table .
: Net Products gained during aerobic respiration per glucose molecule. Stages CO ATP Reduced NAD Reduced FAD Total ATP Production Glycolysis ( ) Link reaction ( ) Krebs cycle ( ) ( ) Total ATPs ATPs ATPs ATPs Figure . : Electron Transport Chain and Terminal Oxidation . pt