Chapter 8, Problem 34A

Summary Introduction

Introduction :

The process that does not occur in the illustrated organelle is glycolysis. Glycolysis is the first stage of cellular respiration that occurs in the cytoplasm of the cell. During glycolysis, one 6 carbon glucose is converted into two molecules of 3 carbon pyruvic acid or pyruvate.

Answer to Problem 34A

Correct answer :

The correct answer is option (A) glycolysis.

Explanation of Solution

Explanation/justification for the correct answer :

Option (A) glycolysis. Glycolysis or Embden, Meyerhof and Parnas (EMP) pathway is the first stage of cellular respiration that occurs in the cytoplasm of every living cell. It does not occur in the mitochondria and is the common process for both anaerobic and aerobic respiration. Thus, the correct answer is an option (A).

The explanation for the incorrect answer :

Option (B) Krebs cycle. Krebs cycle or TCA cycle or citric acid cycle occurs in mitochondrial matrix where enzymes for reactions are present. Citric acid is the first product of Krebs cycle. Thus, this is an incorrect option.

Option (C) conversion of pyruvate to acetyl CoA. Pyruvate is formed in the cytoplasm of the cell then it enters into the mitochondria for further breakdown to acetyl CoA. Thus, this is an incorrect answer.

Option (D) electron transport. Electron transport chain occurs on the inner membrane of the mitochondria, where termination oxidation take place. It produces a large amount of ATPs.  Thus, this is an incorrect answer.