Chapter 23, Problem 23.117EP

Interpretation Introduction

Interpretation: To identify the process that must occur before an ATP molecule produced in oxidative phosphorylation becomes available for cellular use.

Concept introduction: Oxidative phosphorylation is the biochemical process for the synthesis of ATP from ADP and ${\text{P}}_{\text{i}}$. The energy required for the synthesis is transferred from the electron transport chain.

When coenzymes (NADH and FADH₂) gets oxidized, there is proton flow between the matrix and intermembrane space that is responsible for the buildup of ${\text{H}}^{+}$ ions in intermembrane space. The energy released by the proton flow is responsible for the phosphorylation of ADP.