Chapter 12, Problem 12.83EP

Interpretation Introduction

Interpretation: To determine the final electron acceptor in the electron transport chain.

Concept introduction: Electron transport chain is a sequence of biochemical reactions in which electrons and hydrogen atoms from NADH and FADH₂ are transferred to various intermediate carriers and finally leads to the formation of water. The reaction of oxidation of NADH and FADH₂ is:

$\begin{array}{c}\text{NADH}+{\text{H}}^{+}\to {\text{NAD}}^{+}+2{\text{H}}^{+}+2{\text{e}}^{-}\\ {\text{FADH}}_2\to \text{FAD}+2{\text{H}}^{+}+2{\text{e}}^{-}\end{array}$

Energy is lost during the transfer of the electrons from one intermediate carrier to another intermediate carrier and that energy is used for the preparation of ATP from ADP (oxidative phosphorylation).