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40 Cards in this Set

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... are the major components of cell membranes.
phospholipids
phospholipids can also be found in ..., ..., and lung ...
lipoproteins
bile
lung surfactant
the polyunsaturated fatty acids attached to phospholipids can serve as ... for the synthesis of eicosanoids.
precursors
in phospholipids, ... serves as a backbone to which fatty acids and other constituents attach
glycerol
The initial steps in phospholipid synthesis are similar to steps involved in the synthesis of ...
triglycerides
Glycerol 3-phosphate reacts with fatty acyl CoA to form ...
phosphatidic acid
2 different mechanisms are then used to add a ... to the carbon 3 of glycerol
head group
head groups are small, ... groups, usually charged or polar
-ex. choline, ethanolamine, serine, inositol
hydrophilic
In the first mechanism, phosphatidic acid is cleaved by a phosphatase to form diacylglycerol (DAG). DAG then reacts with an activated ...
head group
In the second mechanism, phosphatidic acid reacts with ..., a high energy molecule similar to ATP, to form ...

This molecue then reacts with a head group to produce a glycerophospholipid.
CTP (cytidine 5'-triphosphate)
CDP-diacylglycerol
which glycerophospholipid is this?
-also known as lecithin
-needed by every cell in the body and is a key building block of cell membranes
-important component of the mucus layer in the large intestines
-patients suffering from ulcerative colitis have a disturbed mucosal barrier, and the mucus layers in their large intestines exhibit lower levels of this than that of healthy people.
Phosphotidylcholine
which glycerophospholipid is this?
-found in fish, green leafy veggies, soybeans and rice
-is essential for normal functioning of neuronal cell membranes
-in apotosis, this is transferred to the outer leaflet of the plasma membrane. This is part of the process by which the cell is targeted for phagocytosis.
-This has been used to slow cognitive decline in early-onset Alzheimer's disease
phosphtidylserine
what are the 2 enzymes that arrange phospholipids in membranes?
scramblase
flippase
Which enzyme randomly flips phospholipids across the bilayer to evenly distribute them?
scramblase
which enzyme targets specific phospholipids and flips them across the bilayer?
flippase
sphingolipids are a component of all membranes but are particularly abundant in the ...
myelin sheath
... are thought of to be confusing and enigmatic
sphingolipids
sphingolipids can act as ... communication molecules, antigenic determinants (... blood type), and viral and bacterial ...
intercellular
ABO
receptors
the core of sphingolipids is the long-chain amino alcohol ... (instead of glycerol), which is derived from the AA serine.
-amino acylation with a long chain fatty acid at carbon 2 of this yields a ...
sphingosine
ceramide
the synthesis of sphingolipids begins with formation of ... from serine and palmityl CoA
ceramide
... is the only sphingolipid that is also considered a phospholipid.
It is an important structural lipid component of nerve cell membranes.
sphingomyelin
The glycosphingolipids (the cerebrosides, sulfatides, globosides and gangliosides) are formed through the addition of galactose, glucose, or other ... molecules to the ceramide backbone. (They are produced by adding long carbohydrate chains)
sugar
levels of lecithin (phosphatidylcholine) and sphingomyelin in amniotic fluid are used to assess ...
fetal lung development
lecithin is the major lipid in ..., which reduces water surface tension in alveoli to prevent lungs from collapsing during exhalation.
lung surfactant
-levels of lecithin increase dramatically at # weeks gestation as the fetal lungs reach maturity and begin producing sufficient amounts of surfactant.
-infants born prior to this point may suffer from ...
35
RSD (respiratory distress syndrome or hyaline membrane disease)
Sphingolipids are degraded by lysosomal enzymes. Deficiencies of these enzymes result in a group of lysosomal storage diseases known as the sphingolipidosis due to an inherent defect in ... degradation.
ceramide
These diseases all have defects in ...
tay-sachs disease
gangliosidosis
sandhoff disease
fabry's disease
gaucher's disease
krabbe's disease
niemann-pick disease
farber's disease
ceramide degration
Synthesis of cholesterol occurs primarily in the ..., but also in adrenal glands, ovaries and testes (steroid producing organs)
liver
approximately #% of the body's cholesterol is synthesized de novo (by your cells) from acetyl CoA (the rest comes from your diet)
80%
Cholesterol synthesis occurs in # stages and requires significant reducing power in the form of ...
4
NADPH
In the first stage, acetyl-CoA is converted into ...
-two key enzymes catalyze this conversion: HMG-CoA synthase and ...
-HMG = beta-hydroxy-beta-methylglutaryl CoA
mevalonate
HMG-CoA reductase
the first stage is the rate limiting step in cholesterol synthesis and is therefore the ...

what are some examples of HMG-CoA reductase inhibitors?
major point of regulation

lovastatin/pravastatin
In the second stage, 3 phosphate groups are transferred from ATP to ..., forming 2 activated ... molecules.
mevalonate
isoprene
In stage 3, the 6 activated 5-carbon isoprenes condense to form the 30-carbon ...
squalene
In the 4th stage, squalene is then converted to the 4-ring ... nucleus of cholesterol
steroid
SREBPs (steroid regulator element binding proteins) act as a regulatory ..., controlling expression of key enzymes involved in cholesterol metabolism
transcription factor
HMG-CoA reductase is
... by insulin and thyroxine and ... by glucagon and excess cholesterol
stimulated
inhibited
what are these examples of?
"statins"
niacin/nicotinic acid
bile acid resins
fibric acid derivatives
cholesterol lowering medications
what are the 4 main mechanisms for lipid movement?
-... diffusion
-... between membrane layers
-... lipid-transfer proteins
-... transport carriers
-lateral
-translocation
-cytosolic
-membrane-bound
where are lipids synthesized in the cell?
SER