Chapter 14, Problem 14.72EP

(a)

Interpretation Introduction

Interpretation:

Whether acetoacetyl CoA is (1) a reactant but not a product, (2) a product but not a reactant, or (3) a reactant in one step and a product in another step in ketogenesis has to be determined.

Concept introduction:

Ketone bodies are water-soluble molecules which are synthesized from acetyl CoA through the process of ketogenesis. Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketogenesis involves 4 reaction steps. The first and second step involves condensation, the third step is chain cleavage, and the fourth step is hydrogenation. The molecules formed at the end of each reaction step have a different carbon chain length.

(b)

Interpretation Introduction

Interpretation:

Whether 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) is (1) a reactant but not a product, (2) a product but not a reactant, or (3) a reactant in one step and a product in another step in ketogenesis has to be determined.

Concept introduction:

Ketone bodies are water-soluble molecules which are synthesized from acetyl CoA through the process of ketogenesis. Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketogenesis involves 4 reaction steps. The first and second step involves condensation, the third step is chain cleavage, and the fourth step is hydrogenation. The molecules formed at the end of each reaction step have a different carbon chain length.

(c)

Interpretation Introduction

Interpretation:

Whether acetoacetate is (1) a reactant but not a product, (2) a product but not a reactant, or (3) a reactant in one step and a product in another step in ketogenesis has to be determined.

Concept introduction:

Ketone bodies are water-soluble molecules which are synthesized from acetyl CoA through the process of ketogenesis. Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketogenesis involves 4 reaction steps. The first and second step involves condensation, the third step is chain cleavage, and the fourth step is hydrogenation. The molecules formed at the end of each reaction step have a different carbon chain length.

(d)

Interpretation Introduction

Interpretation:

Whether β-hydroxybutyrate is (1) a reactant but not a product, (2) a product but not a reactant, or (3) a reactant in one step and a product in another step in ketogenesis has to be determined.

Concept introduction:

Ketone bodies are water-soluble molecules which are synthesized from acetyl CoA through the process of ketogenesis. Ketogenesis occurs in the mitochondria of the liver cells. The initial reactants are the molecules of acetyl CoA which are produced by the β-oxidation of fatty acid molecules. Ketogenesis involves 4 reaction steps. The first and second step involves condensation, the third step is chain cleavage, and the fourth step is hydrogenation. The molecules formed at the end of each reaction step have a different carbon chain length.