Triacylglycerol Structure and Storage

What is the yield from the complete oxidation of fatty acids to CO2 and H2O?

9 kcal/g fat

What is the first step in the mobilization of stored fat?

Hydrolytic release of fatty acids and glycerol from TAG

What is the product of hormone-sensitive lipase (HSL) action?

Monoacylglycerol

What is required for hormone-sensitive lipase (HSL) to be active?

Phosphorylation by protein kinase A Signup and view all the answers

What happens to hormone-sensitive lipase (HSL) in the presence of high plasma levels of insulin?

It becomes dephosphorylated and inactivated Signup and view all the answers

What happens to glycerol released during TAG degradation in adipocytes?

It is transported to the liver for phosphorylation Signup and view all the answers

What is the purpose of perilipin phosphorylation by PKA?

To allow translocation and binding of HSL to the droplet Signup and view all the answers

What is the role of adenylyl cyclase in the regulation of hormone-sensitive lipase?

To produce cAMP and activate PKA Signup and view all the answers

What is the function of glycerol 3-phosphate in TAG synthesis?

It is the initial acceptor of fatty acids during TAG synthesis. Signup and view all the answers

Where is glycerol 3-phosphate primarily produced in the body?

Liver Signup and view all the answers

What is the purpose of activating a free fatty acid?

To participate in metabolic processes such as TAG synthesis Signup and view all the answers

What is the primary energy reserve of the body?

TAGs stored in white adipocytes Signup and view all the answers

In which type of cells are TAGs primarily stored?

White adipocytes Signup and view all the answers

What is the purpose of the glucose transporter in adipocytes?

To synthesize TAGs de novo Signup and view all the answers

What happens to TAGs when they are stored in adipose tissue?

They coalesce to form large oily droplets Signup and view all the answers

What is the function of fatty acyl CoA synthetases?

To activate fatty acids for TAG synthesis Signup and view all the answers

What is the energy yield from the oxidation of a molecule of palmitoyl CoA to CO2 and H2O?

129 ATP Signup and view all the answers

What is required for the activation of the fatty acid?

2 ATP Signup and view all the answers

What is the product of the β-oxidation pathway of palmitoyl CoA?

7 NADH and 7 FADH2 Signup and view all the answers

What is the byproduct of the metabolism of certain amino acids?

Propionyl CoA Signup and view all the answers

What is the first step in the metabolism of propionyl CoA?

Carboxylation Signup and view all the answers

What is the coenzyme required for the enzyme propionyl CoA carboxylase?

Biotin Signup and view all the answers

Fatty acids with an odd number of carbons are metabolized by which reaction steps?

The same reaction steps as fatty acids with an even number of carbons Signup and view all the answers

What is the product of the metabolism of propionyl CoA?

D-methylmalonyl CoA Signup and view all the answers

Which enzyme is responsible for cleaving HMG CoA to produce acetoacetate and acetyl CoA?

HMG CoA lyase Signup and view all the answers

Which compound is a volatile, biologically nonmetabolized product that can be released in the breath?

Acetone Signup and view all the answers

What determines the equilibrium between acetoacetate and 3-hydroxybutyrate?

NAD+/NADH ratio Signup and view all the answers

During fatty acid oxidation, which ketone body synthesis is favored due to a low NAD+/NADH ratio?

3-Hydroxybutyrate Signup and view all the answers

Which product is actively removed by its conversion to two acetyl CoAs in ketolysis?

Acetoacetyl CoA Signup and view all the answers

Which enzyme oxidizes 3-hydroxybutyrate to acetoacetate?

3-Hydroxybutyrate dehydrogenase Signup and view all the answers

During fasting, what role do ketone bodies play in the body?

Provide energy to peripheral tissues Signup and view all the answers

Which enzyme provides acetoacetate with a CoA molecule taken from succinyl CoA?

Thiophorase Signup and view all the answers

Which molecule is produced when serine is combined with PA?

phosphatidylserine Signup and view all the answers

What is cardiolipin composed of?

Two molecules of PA esterified with glycerol Signup and view all the answers

Where is cardiolipin predominantly found in eukaryotes?

Inner mitochondrial membrane Signup and view all the answers

What defines a plasmalogen?

A glycerophospholipid with an unsaturated alkyl group at carbon 1 Signup and view all the answers

Which tissue has an abundance of phosphatidalethanolamine?

Nerve tissue Signup and view all the answers

What forms the backbone of sphingomyelin?

Sphingosine Signup and view all the answers

Which constituent of nerve fibers is sphingomyelin particularly important for?

Myelin sheath Signup and view all the answers

What type of linkage attaches a long-chain fatty acid to sphingosine in sphingomyelin?

Amide linkage Signup and view all the answers