Term
what is the structure of a FA? |
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Definition
long hydrocarbon chain and a terminal carboxylate |
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Term
which is a more efficient form of energy: TAG or glycogen |
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Definition
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Term
what is the major energy source in cardiac and skeletal muscle? |
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Definition
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Term
Why does the brain not utilize FA's? |
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Definition
FA's cannot cross the blood brain barrier |
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Term
what is the site of fatty acid oxidation? |
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Definition
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Term
what happens when the hormone lipase is released? |
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Definition
in adipose tissue,hydrolysis of TAG to FA's. |
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Term
when FAs are released into the blood, how does it travel |
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Definition
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Term
how are FA's transported inside the cell |
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Definition
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Term
in the cells, how is acyl-CoA formed for B-oxidation |
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Definition
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Term
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Definition
protein that coats the lipid droplet |
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Term
what is the function of phosphorylated perilipin? |
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Definition
promotes translocation of lipase to lipid droplet for hydrolysis of FA |
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Term
what is the effect of glucagon, epinephrine and ACTH on TAG metabolism? |
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Definition
it activates the release of free fatty acids from triglycerides |
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Term
what is the effect of insulin on TAG metabolism |
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Definition
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Term
what is the name of the enzyme that catalyzes a FA to FA acyl-CoA |
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Definition
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Term
where is FA and FA acyl CoA converted? |
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Definition
outer mitochondrial membrane and ER |
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Term
does the formation of fatty acyl-CoA require ATP? |
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Definition
yes. the hydrolysis of two high energy bonds in ATP |
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Term
what is function of carnitine palmitoyltransferase I? |
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Definition
transports FA to the mitochondrial inner membrane |
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Term
what is the function of translocase? |
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Definition
it takes the intermediate Acylcarnitine into the inner membrane. |
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Term
what effect does malonyl-CoA have CTP and FA oxidation |
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Definition
it inhibits CTP, thus preventing FA oxidation in the fed state. |
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Term
what does the beta oxidation of FA require? |
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Definition
successive cleavage of 2 C w/release of acetyl CoA |
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Term
which FA's diffuse through the membrane |
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Definition
short and medium chain FAs |
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Term
which FA transports through the Carnitine cycle? |
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Definition
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Term
which FA transports through the Carnitine cycle? |
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Definition
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Term
what are the three substances that are collectively known as ketone bodies? |
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Definition
acetoacetone, beta-hydroxybutyrate, acetone |
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Term
this is an important intermediate in the synthesis of cholesterol |
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Definition
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Term
name 4 things that ketone bodies are used for |
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Definition
heart, brain, kidney, skeletal muscle |
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Term
ketone bodies are synthesized to produced |
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Definition
2 acetyl coA going into the TCA cycle |
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Term
the hydrolysis of triglyceride in adipose tissue produces this, which eventually leads to glucose |
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Definition
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Term
what does the liver synthesize glycerol to? by what enzyme? |
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Definition
glycerol 3 phosphate by glycerol kinase |
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Term
what is glycerol 3 phosphate converted to in the liver to undergo gluconeogenesis |
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Definition
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Term
where does omega oxidation of FA occur? |
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Definition
in the ER with involvement of cytochrome P450 |
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Term
what is the prevalent pathway after beta oxidation of FA is defective? |
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Definition
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Term
in omega oxidation, what is introduced on the first step? |
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Definition
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Term
What is the hydroxyl group oxidized to on the omega carbon? |
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Definition
aldehyde and then carboxylic acid |
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Term
what is the end product of omega oxidation? |
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Definition
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Term
what is associated with secondary carnitine deficiency? |
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Definition
defects in the beta oxidation pathway w/accumulation of acylcarnitines, which are secreted in teh urine |
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Term
what are some clinical manifestations of primary carnitine deficiencies? |
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Definition
muscle cramping, muscle weakness |
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Term
what is caused by a primary carnitine deficiency |
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Definition
defect of carnitine transporter |
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Term
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Definition
mutation of the CPTII gene |
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Term
what are the clinical manifestations of CPT deficiency? |
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Definition
muscle weakness during prolonged exercise with loss of myoglobin in the urine |
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Term
how are translocase deficiencies treated? |
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Definition
avoidance of fasting and diet supplemented by medium chain FA |
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Term
what are the clinical symptoms of translocase deficiency |
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Definition
hypoglycemic coma, hyperammoniemia, muscle weakness, cardiomyopathy |
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Term
these inherited disorders affect the first reaction in the B-oxidation of FA |
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Definition
acyl CoA dehydrogenase deficiency |
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Term
what type of dehydrogenases are affected in acyl-CoA dehydrogenases? |
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Definition
short, medium, and very long chain dehydrogenases |
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Term
what is hypoketotic hypoglycemia due to? |
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Definition
a block of B oxidation of FA's which slows gluconeogenesis in the liver. |
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Term
what is dicarboxylic aciduria due to? |
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Definition
accumulation of FA that enter alternative degration pathways such as omega oxidiation. excessive secretion of dicarboxylic acids |
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Term
what is sudden infant death due to? |
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Definition
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Term
where does oxidation of very long chain FA occur? |
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Definition
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Term
|
Definition
failure to oxidize long chain FA |
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Term
What is Zellweger syndrome |
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Definition
inability to make peroxisomes |
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Term
Patients w/zellweger syndrome and XALD have accumulation of what in the blood? |
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Definition
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Term
This antidiabetic drug causes a marked increase in |
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Definition
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Term
beta oxidation in the peroxisome of very long chain FA produces |
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Definition
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Term
With odd-chain FA metabolism via Beta oxidation, what is the product most likely to be? |
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Definition
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Term
where does Alpha oxidation of FA occur? |
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Definition
ER, mitochondria, peroxisomes.
also involves mono oxigenases (P450 family) that use NADH or NADPH |
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Term
what is alhpa oxidation important for? |
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Definition
catabolism of branched chain FA |
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Term
what are the products of alpha oxidation of FA? |
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Definition
3 mols of propionyl-CoA, acetyl CoA and one molecule of isobutyrl CoA |
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Term
what is involved in the reaction of phytanoyl CoA being hydroxylated? |
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Definition
a-ketoglutarate, ascorbate, and iron |
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Term
Refsum's disease is characterized by? |
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Definition
lack of a-hydroxylating enzyme and accumulate phytanic acid |
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Term
what will insulin stimulate in the fed state? |
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Definition
FA synthase, NADPH malic dehydrogenase, and acetyl CoA carboxylase |
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Term
what enzymes do insulin stimulate in the fed state |
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Definition
glut 4 translocation, glucose breakdown to glycerol 3-phosphate for synthesis of TAG.
turns on phosphoprotein phosphatase (removes phosphate from acetyl CoA and activates enzyme)
also stimulates pentose pathway w/generation of NADPH |
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Term
what is the effect of glucagon in the fasted state? |
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Definition
they inhibit acetyl-coA carboxylase, decreasing FA synthesis |
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