Question

All enzymes of $TCA$ cycle are located in the mitochondrial matrix except one which is located in inner mitochondrial membrane in eukaryotes and in cytosol in prokaryotes. This enzyme is –

• A. Succinate dehydrogenase
• B. Lactate dehydrogenase
• C. Isocitrate dehydrogenase
• D. Malate dehydrogenase

Answer 1

The correct option is A Succinate dehydrogenase

Succinate dehydrogenase is the only enzyme of the $TCA$ cycle, which is present in the inner mitochondrial membrane. It is also a part of the electron transport chain. It forms the complex II of the electron transport chain. It produces $FAD{H}_2$ during oxidation of succinate to fumarate as $FA{D}^{2+}$ gets reduced to $FAD{H}_2$. $FAD{H}_2$ enters the electron transport chain and transfers the electrons to ubiquinone, which transfers the electrons further to cytochrome c.
So, the correct answer is option 'a'.