FInal W2 Flashcards
The advantages of lipids as a storage is that it is a highly ___ form of carbon, stored without ___, does not result in an increase in ____, and it’s ___ means its stable as a storage molecule
reduced, hydration, osmolarity, inertness
Disadvantages of lipids as storage is that it’s insolubility requires _____ and ___, and the stable C-C bonds require _____
emulsification, transport, activation
When dietary fats are ingested, they are emulsified into ___ by __ ___. Then intestinal ____ hydrolyze TAGs to free fatty acids and _____. These products are then transported into intestinal ____, where TAGs are resynthesized and packaged into ____.
micelles, bile salts, lipases, monoglycerols, enterocytes, chylomicrons
Lipids are ___ within the aqueous digestive contents. Bile salts are __ ___ that make lipids into micelles. The ___ bonds within the TAG orient themselves at the micelle ___ increasing accessibility by lipases
insoluble, amphipathic emulsifiers, ester, surface
macromolecular complexes of specific carrier proteins and various combinations of phospholipids, cholesterol, cholesterol esters and TAGs
lipoproteins
Chlyomicrons transport dietary ____ to ___ tissues. They have a ___ core rich in TAG and a ____ surface containing ____ and ____
TAGs, peripheral, hydrophobic, hydrophilic, phospholipids, apolipoproteins
Chylomicrons are then transported to peripheral tissues through the ___. At target tissues, TAGs are ___ to free FAs and ____. These products are taken up by the cells. FAs are stored in _____ tissue or ___ in ____ for energy
blood, hydrolyzed, monoacylgylcerol, adipose, oxidized, muscle
Lipids are stored in __ ___ within adipocytes. Lipid droplets contain a ___ core of TAG and ____ _____ surrounded by a monolayer of ____. The surface of the lipid droplets are coated with ___ which function to restrict ____.
lipid droplets, hydrophobic sterol esters, phospholipids, perilipins, mobilization
When we need to use fat stored in adipose tissue, ___ binds to receptors on the adipocyte. ___ ___produces cAMP which activates PKA. This phosphorylates ____ and perilipin. ___ dissociates from perilipin and ____ metabolize TAG to glycerol and free FAs. These products are then transported by __ __ in blood. They then dissociate from them and enter target cells through ___ ___ ___. The free FAs are then ___ for fuel in target cells
glucagon, adenylyl cyclase, HSL, CGI-58, serum albumin, plasma membrane transporters, oxidized
Very low density lipoproteins or ____, are rich in TAG and transport ___ lipids from the ___ to peripheral tissues
VLDL, endogenous, liver
Low density proteins or _____, transport ___ and _____ between the liver and peripheral tissues
LDL, cholesterol, cholesterol esters
High density lipoproteins or ____, transport cholesterol and cholesterol esters from ___ tissues back to the liver
HDL, extrahepatic
Each class of lipoprotein has a specific function which is determined by its point of ___, lipid ____ and ___ content
synthesis, composition, apolipoprotein
Describes the transport of dietary lipids within chylomicrons to extrahepactic tissues and uptake of chylomicron remnants in liver
exogenous pathway
after free FAs are released into tissues, chylomicron remnants are ___ by the __ and degraded within ____.
endocytosed, liver, lysosomes
describes the transport of lipids between the liver and peripheral tissues by VLDL and LDL
endogenous pathway
Excess lipids are ___ to TAG and __ ___ within the liver, p into ____ the blood. __ catalyze the release of free FAs which are taken up by peripheral tissues for ___ or energy. The loss of TAG from VLDL produces ____ which bind to receptors within ___ tissues, mediating uptake. The ones not uptaken return to the ____
metabolized, cholesterol esters, lipases, storage, LDL, peripheral, liver
Describes the transport of excess cholesterol in extrahepatic tissues back to the liver as HDL
reverse cholesterol transport
HDL is produced by the _____ and accumulates ____ ____ from chylomicron and ___ remnants and ____ cells. HDL returns cholesterol esters to the ____, while some are transferred to ___ by cholesterol ester __ ____
liver, cholesterol esters, VLDL, extrahepatic, liver, LDL, transfer protein
describes the synthesis, secretion, and reabsorption of bile salts by the liver and gallbladder
enterohepatic circulation
Catalyzes the formation of cholesterol esters from cholesterol and lecithin
LCAT
the buildup of fats, cholesterol and other substances on artery walls forming a plaque that restricts blood flow or bursts, leading to a blood clot
atherosclerosis
Oxidation of fatty acids is a central ____ pathway in many organisms and tissues. ___% of daily energy requires are provided by dietary ____
energy-yielding, 40, TAG
Free fatty acids in the cytosol are activated by _____ ____ ____ to form fatty acyl-CoA. The formation of this product is made energetically favorable by hydrolysis of 2 high energy ______ _____. Fatty acyl-CoAs can be transported into the _____ and oxidized or used within the cytosol to synthesize ___ _____. The overall reaction has a gibbs free energy of _____kj/mol
fatty acyl-CoA synthetase, phosphodiester bonds, mitochondria, membrane lipids, -34
Fatty acyl-CoA destined for mitochondria must be attached to ___ to be shuttled across the inner mitochondrial _____. This product is transported through the ____/___ ____
carnitine, acyl-carnitine, carnitine cotransporter
Oxidation of fatty acids occurs in 3 stages. In ____ ___ fatty acids undergo oxidative removal or ___ units to form acetyl-CoA. In the citric acid cycle, acetyl-coa is oxidized to ____. In oxidative phosphorylation, reduced __ __ are oxidized in the ETC driving synthesis of ___
beta oxidation, 2C, CO2, electron carriers, ATP
The first step of beta oxidation is the ___ of fatty acyl-CoA, producing a ____ bond between alpha and beta carbons, producing _______. This is catalyzed by ____ ____.
dehydrogenation, double, trans-2-enoyl-CoA, acetyl-CoA dehydrogenases
In step 2 of the beta oxidation pathway, ___ is added across the double bond between the alpha and beta carbons to form ________. This is catalyzed by _____
H2O, L-beta-hydroxy-acyl-CoA, enoyl-CoA hydratase
In step 3 of beta oxidation, L-beta-hydroxyacyl-CoA is dehydrogenated to form ____. This is catalyzed by ____ -___
beta-ketoacyl-CoA, beta-hydroxyacyl-CoA, dehydrogenase
In step 4 of beta oxidation, beta-ketoacyl-CoA reacts with a molecule of free ___ forming ___ and ___, shortened by ___ carbons from the ___ end
CoA, acetyl-CoA, acyl-CoA, 2, carboxyl
The single bonds between ____ groups within fatty acids are relatively ____. Acyl-CoAs have an alpha carbon bound to 2 ____ carbons, which makes the beta carbon a good target for ___ attack, and ______ a good leaving group
methylene, stable, carbonyl, nucleophilic, CH2COCoA
Complete oxidation of ____ fatty acids requires additional reactions
unsaturated
___ chain fatty acid oxidation yields _____ and _____. The latter is metabolized by a separate pathway within the ___ ____
odd, acetyl-CoA, propionyl-CoA, mitochondrial matrix
propionyl-CoA is carboxylated to form _____. This is catalyzed by ____ ___ and requires ATP. Then ______ is enzymatically epimerized to _____ catalyzed by methylmalonyl-CoA epimerase. Then L-methylmalonyl-CoA is rearranged to ____, catalyzed by methylmalonyl-CoA mutase, and enters the citric acid cycle
methylmalonyl-CoA, propionyl-CoA carboxylase, D-methylmalonyl-CoA, L-stereoisomer, succinyl-CoA
within mammals, ___ are much more active on long chain fatty acids and ______ chain fatty acids. The pathways are similar except the first oxidation produces ___. Several ____ ____ are unique to this organelle
peroxisomes, branched, H2O2, auxiliary enzymes
the glycerol released by lipases are metabolized to _______ and enters __ in the liver
D-glyceraldehyde, glycolysis
