Question

A false statement regarding cytochrome c-oxidase complex in ETS in mitochondria is:

• A. Receives electrons directly from ubiquinone
• B. Capable of reducing $O_2$
• C. Extends across the thickness of mitochondrial membrane
• D. Contains Fe & Cu both

Answer 1

The correct option is A Receives electrons directly from ubiquinone

In electron transport chain, ubiquinone accepts electrons from complex I and complex II and delivers them to complex III. Then, complex III pumps protons through the membrane and passes its electrons to cytochrome c for transport to the fourth complex, cytochrome c-oxidase. Cytochrome c-oxidase, a transmembrane protein, has two heme groups containing iron and two copper-containing centres. It ultimately transports the electrons to molecular oxygen, forming water.