Lipid Metabolism during Fasting

<p>Peroxins (D)</p> Signup and view all the answers

<p>In the cytosol (B)</p> Signup and view all the answers

<p>Impaired peroxisome function (D)</p> Signup and view all the answers

<p>Mutations that inactivate both copies of specific PEX genes (B)</p> Signup and view all the answers

<p>Cellular apoptosis (C)</p> Signup and view all the answers

<p>High forehead (C)</p> Signup and view all the answers

<p>Hypomyelination (B)</p> Signup and view all the answers

<p>Impaired organ function (B)</p> Signup and view all the answers

<p>Mental retardation is common. (D)</p> Signup and view all the answers

<p>They must be activated (D)</p> Signup and view all the answers

<p>It generates more ATP per carbon than sugars. (A)</p> Signup and view all the answers

<p>Progressive loss of vision and hearing (B)</p> Signup and view all the answers

<p>Floppy appearance due to hypotonia (D)</p> Signup and view all the answers

<p>Breaking down hydrogen peroxide into water (B)</p> Signup and view all the answers

<p>Lysosomes are formed in the Golgi complex, whereas peroxisomes self-replicate. (B)</p> Signup and view all the answers

<p>Oxidation of toxic compounds (D)</p> Signup and view all the answers

<p>Peroxisomes lack internal DNA molecules. (B)</p> Signup and view all the answers

<p>Microbodies (C)</p> Signup and view all the answers

<p>Active transport using specific targeting signals (D)</p> Signup and view all the answers

<p>Production of ATP (B)</p> Signup and view all the answers

<p>Peroxisome biogenesis understanding (C)</p> Signup and view all the answers

<p>One NADH, one FADH2, one Acetyl-CoA, and a fatty acid shortened by two carbons (B)</p> Signup and view all the answers

<p>Thiolase (B)</p> Signup and view all the answers

<p>The third reaction resembles the malate dehydrogenase reaction of the citric acid cycle. (D)</p> Signup and view all the answers

<p>In the matrix of the mitochondrion, where it is oxidized in the citric acid cycle (D)</p> Signup and view all the answers

<p>Its deficiency can lead to improper fatty acid oxidation, potentially linked to SIDS. (C)</p> Signup and view all the answers

<p>They accumulate in the blood and organs due to compromised breakdown. (A)</p> Signup and view all the answers

<p>PPAR-α (B)</p> Signup and view all the answers

<p>They are downregulated, impairing fatty acid metabolism. (C)</p> Signup and view all the answers

<p>Breakdown of very long chain fatty acids (C)</p> Signup and view all the answers

<p>Lipotoxicity and mitochondrial damage (D)</p> Signup and view all the answers

<p>Insulin resistance allows for increased levels of FFAs in the blood. (A)</p> Signup and view all the answers

<p>To decompose hydrogen peroxide to oxygen and water (B)</p> Signup and view all the answers

<p>Lipolysis is inhibited, resulting in decreased energy availability. (B)</p> Signup and view all the answers

Breakdown of fats (lipolysis) is increased during fasting to provide energy.

Insulin normally inhibits lipolysis (fat breakdown), while in sepsis, insulin resistance overrides this inhibition, allowing lipolysis.

Breakdown of fatty acids (Beta-oxidation) is impaired during sepsis, leading to accumulation of FFAs in organs (and blood).

PPAR-α, a transcription factor, is upregulated in fasting, stimulating fat breakdown.

In sepsis, PPAR-α is downregulated, preventing adequate fat breakdown—opposite to fasting.

Peroxisomes are organelles that break down very long-chain fatty acids (VLCFAs).

Sepsis causes a shortage of energy due to impaired fatty acid breakdown, resulting in potential organ damage.

VLCFAs are broken down to MCFA's, then sent to mitochondria for complete breakdown into CO2 and water in animals; this is exclusively done in peroxisomes in plants & yeast.

Organelles that break down harmful substances like hydrogen peroxide in cells.

Peroxisomes convert hydrogen peroxide to water, making it harmless.

Peroxisomes import proteins from the cytosol needed for their reproduction.

Specific amino acid sequences that direct proteins to peroxisomes.

Detoxify alcohol and harmful compounds in liver cells.

Peroxisomes help create phospholipids used in membrane formation.

Older name for organelles now referred to as peroxisomes and lysosomes.

Another type of microbody, formed in the Golgi complex, distinct from peroxisomes through origin.

An autosomal recessive disorder caused by mutations in genes encoding peroxins, proteins responsible for peroxisome assembly.

Proteins needed for building and maintaining peroxisomes.

Genes that code for peroxins.

Very long chain fatty acids, usually broken down by peroxisomes.

Branched chain fatty acids, usually broken down by peroxisomes.

The division of a peroxisome into two daughter peroxisomes.

The process of proteins being brought inside and inserted in the peroxisome membrane.

Fatty acid oxidation occurs in four sequential steps, each catalyzed by a different enzyme, each step generates energy-carrying molecules, and shortens the fatty acid by two carbons.

The first step of beta-oxidation, involving oxidation, which forms a trans intermediate.

This step in beta-oxidation is similar to a citric acid cycle reaction (fumarase).

This step in beta-oxidation mirrors another citric acid cycle reaction (malate dehydrogenase).

The final step in beta-oxidation involves the enzyme 'thiolase' and generates Acetyl-CoA.

Genetic conditions affecting peroxisomes, organelles crucial for various metabolic processes.

Distinctive facial features like high forehead, frontal bossing, small face seen in peroxisomal disorders.

Decreased muscle tone, often a symptom of certain disorders.

Reduced levels of myelin, a protective layer around nerve fibers in the central nervous system.

The breakdown of fatty acids to produce energy (ATP).

A specific metabolic pathway for breaking down fatty acids, 2 carbons at a time.

The preparation step before fatty acid oxidation, requiring energy.