In citric acid cycle decarboxylation occurs when

Options

A. Citric acid converts to `alpha` - ketoglutaric acid
B. Succinic acid converts to malic acid
C. Malic acid converts to oxaloacetic acid
D. Oxaloacetic acid converts to citric acid

Answer

A

Explanation

Citric acid `underset("Isocitrate dehydrogenase" )overset(NAD^(+) rarr NADH_2)rarr` Oxalosuccinic acid `overset("Decarboxylase ")underset(CO_2)rarr 5alpha` ketaglutaric acid
* Isocitrate is changed into oxalosuccinic acid one a molecule of `NADH_2` Produced.
* Then oxalosuccinate (6C) is converted into `alpha` - ketoglutaric acid (5C) . During this step `CO_2` is released and `NAD^(+)` is reduced to `NADH^(+) H^+`