Question

Cytochrome which hands over electrons to oxygen during terminal oxidation is

• A. Cyt b
• B. Cyt a
• C. Cytc
• D. Cyt ${\alpha }_3$

Answer 1

The correct option is D Cyt ${\alpha }_3$

The terminal oxidation is the last step of electron transport chain in which electrons from cytochrome c are transferred via cyt. a and cyt. a3 to oxygen. The reaction is catalyzed by cytochrome oxidase enzyme which is tightly bound to the inner mitochondrial membrane. It contains inseparable cyt. a and cyt. a3 components and also some polyp[eptide that contain two copper ions. Both iron and copper undergo reversible changes in their oxidation states during electron transport by cytochrome oxidase.

Thus, the correct answer is option D.