Question

Complex III and IV of the $ETS$ are respectively

• A. Cytochrome $c$ oxidase and cytochrome $b{c}_1$ complex
• B. Cytochrome $b{c}_1$ complex and cytochrome $c$ oxidase
• C. $FAD{H}_2$ and cytochrome $c$ oxidase
• D. $NADH$ dehydrogenase and $FAD{H}_2$

Answer 1

The correct option is B Cytochrome $b{c}_1$ complex and cytochrome $c$ oxidase

Electron transport chain

The electron transport chain is present in the mitochondria and it is composed of four protein complexes. These complexes are:

• Complex I - NADH-coenzyme Q oxidoreductase or NADH dehydrogenase
• Complex II - Succinate-Q oxidoreductase
• Complex III - Cytochrome bc1 complex or Coenzyme Q-cytochrome c reductase
• Complex IV - Cytochrome C oxidase

Electrons pass through one complex to another in a sequence with the help of cytochromes and other enzymes.

Final answer:

(D) Cytochrome $b{c}_1$ complex and cytochrome $c$ oxidase