Lipid Metabolism (II)

These flashcards cover key concepts related to lipid metabolism, including fatty acid degradation and synthesis, regulatory mechanisms, and metabolic pathways.

What is the main oxidative process that converts a fatty acid to acetyl CoA during fatty acid degradation?

The process includes oxidation, hydration, oxidation, and cleavage.

What are the four steps of fatty acid degradation?

Activation, transport, beta-oxidation, and cleavage into acetyl-CoA.

Which molecule is produced from the final round of beta-oxidation of odd-chain fatty acids?

Propionyl CoA.

Which enzyme catalyzes the first step of beta-oxidation?

Acyl-CoA dehydrogenase.

What is the role of carnitine in fatty acid metabolism?

Carnitine helps transport long-chain fatty acyl-CoA into the mitochondria.

What is the fate of acetyl-CoA produced from beta-oxidation?

It enters the citric acid cycle.

What are the end products of beta-oxidation?

Acetyl-CoA, NADH, and FADH2.

What is the energy yield from one molecule of acetyl-CoA fully oxidized in the Krebs cycle?

12 molecules of ATP.

What regulates fatty acid biosynthesis involving acetyl-CoA carboxylase?

Allosteric regulation by palmitoyl-CoA and citrate, and covalent regulation via phosphorylation.

How is malonyl-CoA formed for fatty acid synthesis?

From acetyl-CoA and bicarbonate through the action of acetyl-CoA carboxylase.

What is the primary location for de novo fatty acid synthesis?

Cytoplasm.

Which reaction is the rate-limiting step in fatty acid biosynthesis?

The reaction catalyzed by acetyl-CoA carboxylase.

What happens to carnitine in the body?

75% comes from diet, and the rest is synthesized in the liver and kidney.

What characterizes carnitine deficiency?

It can lead to serious disorders in the myocardium, liver, and nervous system.

What is palmitate?

Palmitate is a normal product of the animal fatty acid synthase pathway, with the chemical formula 16:0.