Question

multiple choice question

which component of the electron transport system accepts electrons from nadh?

complex iii
cytochrome c
complex i
complex ii
coenzyme q
complex iv

Explanation:

Identify the entry point of electrons from NADH

In the mitochondrial electron transport chain, NADH is oxidized back to \( \text{NAD}^+ \) by transferring its two high-energy electrons to Complex I (NADH dehydrogenase).

Evaluate the other options

• Complex II receives electrons from \( \text{FADH}_2 \) via succinate.
• Coenzyme Q (ubiquinone) receives electrons from both Complex I and Complex II.
• Complex III receives electrons from reduced Coenzyme Q.
• Cytochrome c transfers electrons from Complex III to Complex IV.
• Complex IV transfers electrons to the final electron acceptor, oxygen.

Answer:

• Complex III
• Cytochrome c
• Complex I (Correct answer)
• Complex II
• Coenzyme Q
• Complex IV