Lipid Biosynthesis
50 questions available
Questions
What is the irreversible process that commits acetyl-CoA to fatty acid synthesis, and what enzyme catalyzes it?
View answer and explanationIn the mammalian fatty acid synthase I (FAS I) system, what is the role of the acyl carrier protein (ACP)?
View answer and explanationWhat is the net equation for the synthesis of one molecule of palmitate from 8 molecules of acetyl-CoA?
View answer and explanationIn nonphotosynthetic eukaryotes, how is acetyl-CoA, the precursor for fatty acid synthesis, transported from the mitochondria to the cytosol?
View answer and explanationWhat is the primary mechanism by which citrate regulates fatty acid synthesis in vertebrates?
View answer and explanationHow do mammals synthesize the monounsaturated fatty acid oleate, 18:1(delta9)?
View answer and explanationWhich class of molecules, derived from 20-carbon polyunsaturated fatty acids, are considered short-range signaling molecules that mediate inflammation, pain, and fever?
View answer and explanationWhat is the common metabolic precursor for the synthesis of both triacylglycerols and glycerophospholipids in animal tissues?
View answer and explanationHow does insulin promote the conversion of carbohydrate to triacylglycerols?
View answer and explanationWhat is the primary role of the triacylglycerol cycle that operates between adipose tissue and the liver, especially during fasting?
View answer and explanationWhat is the main source of glycerol 3-phosphate for triacylglycerol synthesis in adipose tissue, especially during fasting?
View answer and explanationIn eukaryotic cells, where does the synthesis of cardiolipin and phosphatidylinositol primarily occur?
View answer and explanationWhat is the activated intermediate used for the synthesis of phosphatidylinositol and cardiolipin in eukaryotes?
View answer and explanationWhat are the four main stages of cholesterol biosynthesis from acetyl-CoA?
View answer and explanationWhat is the energetic cost, in terms of ATP molecules, to synthesize one molecule of squalene from acetyl-CoA?
View answer and explanationWhich enzyme is the major point of regulation in the cholesterol biosynthesis pathway and is the target of statin drugs?
View answer and explanationWhat is the function of low-density lipoprotein (LDL)?
View answer and explanationIn the context of familial hypercholesterolemia (FH), what is the primary defect that leads to very high blood levels of cholesterol?
View answer and explanationWhat is the primary function of high-density lipoprotein (HDL) in cholesterol transport?
View answer and explanationHow do sterol regulatory element-binding proteins (SREBPs) regulate cholesterol synthesis in response to low cellular sterol levels?
View answer and explanationWhat is the common intermediate that is condensed to form porphobilinogen in the synthesis of heme?
View answer and explanationWhat is the role of ferrochelatase in heme synthesis?
View answer and explanationIn the degradation of heme, what is the immediate green-colored precursor to the yellow-colored bilirubin?
View answer and explanationWhat is the function of the enzyme cyclooxygenase (COX), also known as prostaglandin H2 synthase?
View answer and explanationWhat is the biochemical basis for the different physiological roles of the COX-1 and COX-2 isozymes?
View answer and explanationWhat is the primary product of the mammalian fatty acid synthase I (FAS I) system?
View answer and explanationIn eukaryotes, the synthesis of phosphatidylcholine can occur through the Kennedy pathway. What is the activated intermediate that condenses with diacylglycerol in this pathway?
View answer and explanationIn sphingolipid synthesis, what are the initial two reactants that condense to form the backbone of sphinganine?
View answer and explanationWhich of the following molecules serves as the activated donor of the phosphocholine head group in the synthesis of sphingomyelin in animals?
View answer and explanationWhat is the source of the oxygen atom that forms the ether linkage in plasmalogen synthesis?
View answer and explanationWhich molecule is formed from the head-to-head condensation of two molecules of farnesyl pyrophosphate?
View answer and explanationWhat is the primary role of apolipoprotein C-II (apoC-II)?
View answer and explanationThe drug rosiglitazone (Avandia) is a thiazolidinedione used to treat type 2 diabetes. What is its mechanism of action related to lipid metabolism?
View answer and explanationIn the four-step repeating sequence of fatty acid synthesis, what is the source of reducing power for the two reduction steps?
View answer and explanationWhat is the function of the thioesterase (TE) domain of the mammalian fatty acid synthase I?
View answer and explanationMammals cannot synthesize linoleate (18:2) and alpha-linolenate (18:3). Why are these considered essential fatty acids?
View answer and explanationWhat is the mechanism by which aspirin inhibits the synthesis of prostaglandins?
View answer and explanationWhat are the two activated isoprene units that are central to cholesterol formation?
View answer and explanationIn the four-stage pathway of cholesterol synthesis, the conversion of which linear molecule to a four-ring structure is a key step?
View answer and explanationWhat is the primary carrier of newly synthesized triacylglycerols and cholesterol from the liver to peripheral tissues in the endogenous pathway of lipid transport?
View answer and explanationHow is the uptake of LDL by peripheral cells primarily mediated?
View answer and explanationWhat is the function of the enzyme lecithin-cholesterol acyl transferase (LCAT)?
View answer and explanationHow does the transcription factor LXR (Liver X receptor) contribute to cholesterol homeostasis when cellular cholesterol levels are high?
View answer and explanationIn the condition atherosclerosis, what are foam cells?
View answer and explanationWhat is the final linear precursor that undergoes cyclization to form the steroid nucleus in cholesterol biosynthesis?
View answer and explanationBesides cholesterol, what other important biological molecules are derived from isopentenyl pyrophosphate?
View answer and explanationWhat is the initial source of the two-carbon units that are added to a growing fatty acid chain during its synthesis?
View answer and explanationWhat is the function of the genetic disease Niemann-Pick type-C (NPC)?
View answer and explanationWhat is the role of the APOE4 allele in human health?
View answer and explanationHow many molecules of acetyl-CoA are required to form the six-carbon intermediate, beta-hydroxy-beta-methylglutaryl-CoA (HMG-CoA), in the first stage of cholesterol biosynthesis?
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