Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
|
What is beta oxidation, where does it occur?
|
It is the oxidation pathway that burns FA
Very Long chain FA can only be burned in peroxisomes Long, medium, and short can be burned in Mito |
|
|
How are fatty acids trapped inside cells, what enzymes are used to do this and where are these enzymes located?
|
Fatty Acyl-CoA synthase is the enzyme that traps FA
Trapped by adding CoA to the FA Two steps – ATP added (as AMP) and then CoASH added (as CoA) |
|
|
What compound is needed to move long-chain fatty acids into the mitochondrial matrix?
|
Carnitine is used to move long chain FA into the mitochondria
|
|
|
How is beta-oxidation in the mitochondria regulated?
|
regulated by Malonyl CoA
Malonyl CoA inhibits Carnatine Palmitoyl Transferase I (CPTI) which causes the addition of Acetyl CoA to Carnitine |
|
|
What is the most common genetic defect in fatty acid oxidation, what problems does it cause and how can it be detected at birth?
|
Medium chain Acyl CoA dehydrogenase (MCAD)
Causes hypoketotic hypoglycemia Vomiting and lethargy after fasting in a child 3-15 months |
|
|
What product is produced by the beta-oxidation of odd chain fatty acids and what vitamin is required for the conversion of this compound to glucose in the liver?
|
Odd-chain FA produce Propionyl CoA
Requires B12 to convert it to glocose |
|
|
What is alpha-oxidation?
|
Occurs in peroxisomes
Handles odd carbon FA with methyl side chains (phytanic acid from chlorophyll) |
|
|
what are the three end products that come from the alpha-oxidation of this compound?
|
Acetyl CoA
Propionyl CoA Isobutyryl CoA |
|
|
Compare beta-oxidation in mitochondria with beta-oxidation in peroxisomes:
Peroxisomes |
10% of all beta oxidation
Carnitine transport not needed Produce H2O2, NADH, and Acetyl CoA Handle very long chain FA No ATP production |
|
|
Compare beta-oxidation in mitochondria with beta-oxidation in peroxisomes:
Mitochondria |
Produces ATP and NADH and CO2
Carnitine needed |
|
|
What is omega-oxidation?
|
Oxidation that starts at the farther most Carbon
Used to improve water solubility for the excretion in urine |
|
|
where does Omega-Oxidation occur?
|
Occurs in the ER using a mixed function oxidase
|
|
|
what two vitamins and class of lipid are metabolized using omega-oxidation?
|
Works on Eicosanoids, Vitamin E, and Vitamin A
|
|
|
What are ketone bodies?
|
Ketone bodies are formed from generation of large quantities of Acetyl-CoA in the liver
Ketone bodies can be formed from any aa and this can occur in any tissue |
|
|
what conditions are needed for the production of Ketone Bodies?
|
Starvation
Severe DM (??) Rapid mobilization of fat Need a high rate of beta oxidation in the liver to form them |
|
|
Where and why are ketones used to produce energy?
|
Used as energy by the heart, skeletal muscle, kidney and brain
Acetyl-CoA is used to make glucose for the brain |
|
|
What conditions are needed for severe ketoacidosis to occur?
|
An insulin deficiency and a glucagon excess cause accelerated ketogenesis
|
|
|
what kind of increase in blood and urine levels of ketone bodies occur during severe ketosis?
|
Excreted levels of ketones are 40 times higher in the urine and 30 times higher in the blood
|
|
|
What 4 conditions can result in enough ketone body production to cause death?
|
Uncontrolled diabetes mellitus (Type I without insulin – 3%)
Septic Shock (Type II) Myocardial Infarction (Type II) Pregnancy |
