Chapter 13, Problem 5Q

Summary Introduction

To explain: How the statement “The oxygen consumed during the oxidation of glucose in animal cell is returned as part of CO₂ to the atmosphere” is experimentally proved to be wrong.

Introduction: The initial stage of oxidation of glucose takes place in the cytosol in glycolysis process. In this process, molecular oxygen is not used, and a little amount of energy in form of ATP is released. In this process, a three-carbon compound and pyruvate are produced as end products. In aerobic respiration, the pyruvate formed in the glycolysis is transported into the mitochondria, where oxidation of glucose takes place in the presence of oxygen to form carbon dioxide (CO₂).