Question

Which among the following enzymes is common for both Krebs cycle and electron transport chain?

• A. Citrate dehydrogenase
• B. Malate dehydrogenase
• C. Fumarate dehydrogenase
• D. Succinate dehydrogenase

Answer 1

The correct option is D Succinate dehydrogenase

In aerobic respiration, succinate dehydrogenase is used both in Krebs cycle and electron transport chain (ETC).

In Krebs cycle, it catalyses the conversion of succinate to fumarate.

In the electron transport chain, it is the main constituent of complex II. It acts as an electron receiver and accepts electrons from ${\mathrm{FADH}}_2$ and transfers the electrons to complex III.