Chapter 23, Problem 72P

Interpretation Introduction

Interpretation:

The fate of an acetyl CoA molecule after several turns of the citric acid cycle should be determined.

Concept Introduction:

Aerobic respiration occurs in two steps:

• Glycolysis
• Citric acid cycle

Glycolysis is the first step that forms pyruvate as given below:

  ${\text{Glucose + 2ATP + 2NAD}}^{\text{+}}{\text{ + 4ADP + 2P}}_{\text{i}}\stackrel{}{\to }{\text{ 2 Pyruvate + 4ATP + 2NADH + 2H}}^{\text{+}}$

In the presence of oxygen means aerobic respiration, this pyruvate enters in the Krebs cycle and extracts energy in the form of electrons transfer. Electrons are transferred from the pyruvate to the receptors like NAD⁺, GDP, and FAD and CO₂ gas is formed as the waste product.