Biochem - Final - Part 3

davidwurbel7's version from 2015-04-19 23:16

Fatty Acid Synthase Complex (FAS Complex)

Question Answer
The first reaction of FAS Complex is a _________ reactionCondensation/Decarboxylation
The second reaction of FAS Complex is a _______ reactionReduction
The third reaction of FAS Complex is a ________ reactionDehydration
The fourth reaction of FAS Complex is a _________ reactionReduction

Fatty Acid Structure

Question Answer
An ω6 fatty acid with a structure of 18:2, Δ9,12Linoleic Acid
An ω3 fatty acid with a structure of 18:3, Δ9,12,15Linolenic Acid
Synthesized from linoleic acid with a structure of 20:4, Δ5, 8,11,14Arachidonic Acid
Precursor of prostaglandins and thromboxanesArachidonic Acid
Synthesized from linolenic acid with a structure of 20:5, Δ5, 8, 11, 14, 17Eicosapentaenoic Acid
Precursor of a class of eicosanoidsEicosapentaenoic Acid

Triacylglycerol Synthesis

Question Answer
Activation of fatty acid is catalyzed by _________ which required two high-energy phosphatesAcyl CoA Synthetase (Thiokinase)
Glycerol-3-phosphate is synthesized in liver and adipose tissue by ____________ from dihydroxyacetone phosphate (DHAP) synthesized from glucoseGlycerol Phosphate Dehydrogenase
Only in the liver, glycerol is converted to glycerol-3-phosphate byGlycerol Kinase

Cholesterol and Cholesterol Synthesis

Question Answer
What organ is cholesterol primarily synthesized inLiver
All 27 carbons present in cholesterol are derived from one precursorAcetyl CoA
Acetyl CoA is convert to _________ which is the starting substrate of cholesterol synthesisMevelonate
Catalyzed step is committed and rate determining for cholesterol biosynthesisHMG CoA Reductase
Active when in a dephosphorylated state and regulated by reversible phosphorylationHMG CoA Reductase
Statins drugs inhibitHMG CoA Reductase
Insulin binds to protein phosphatase which dephosphorylates ______ activating itHMG CoA Reductase
Has a negative effect on HMG CoA ReductaseMevelonate
Final end product and bile acid products have a negative effect on HMG CoA ReductaseCholesterol
If high level of cholesterol in the cytoplasm, cholesterol production in inhibited by cholesterol binding toSCAP
With SCAP not bound by cholesterol, this DNA-binding domain moves into the nucleus and induces transcriptionSREBP
The three fates of this molecule is to become cholesterol, CoQ, or dolicholFarnesyl Pyrophosphate (FPP)
Catalyzes the transfer of a fatty acid from coenzyme A to the hydroxyl group on carbon 3 of cholesterol producing a cholesterol esterAcyl CoA-Cholesterol Acyl Transferase (ACAT)
This vitamin is also loaded onto APO-B100 with cholesterol esters during formation of VLDLVitamin E
Can be converted into cholesterol ester, biliary cholesterol, or bile acidsHepatic Cholesterol

Fates of Cholesterol

Question Answer
The rate limiting enzyme of bile salts and bile acids7α-hydroxylase
Cholyl CoA and Chenodeoxycholyl CoA are derived from7α-hydroxycholesterol
Bile acid with a pKa of 2Taurocholic Acid and Taurochenodeoxycholic Acid
Bile acid with a pKa of 4Glycocholic Acid and Glycochenodeoxycholic Acid
Bile acid with a pKa of 6Cholyl-CoA and Chenodeoxycholyl-CoA
There are how many primary bile acids4
There are how many secondary bile acid2
95% of all bile acids and salts are reabsorbed in the Ilium. The major component of the 5% that is lost is composed ofLithocholic Acid
A lipid soluble, mobile complex present in the electron transport chainUbiquinone (Coenzyme Q, CoQ)
Found in higher quantities in organs with the highest energy requirements—such as the heart, neurons, liver and kidneyUbiquinone (Coenzyme Q, CoQ)
A polyprenol, a product of HMG-CoA reductase making mevalonate and subsequently farnesyl pyrophosphateDolichol
Plays a role in the co-translational N-glycosylation of proteoglycans and glycoproteinsDolichol
Converted into progesterone which can be converted into any of the following; cortisol, corticosterone which can then be converted into aldosterone, testosterone which can then be converted into estradiolCholesterol

Lipoprotein Metabolism

Question Answer
Lowest density of lipoproteinChylomicrons
Highest density of lipoproteinLp(a)
Based on electrophoretic mobility, this lipoprotein is called alphaHDL
Based on electrophoretic mobility, this lipoprotein is called betaLDL
The name of the apolipoprotein necessary for formation of chylomicronsApo B-48
Another apolipoprotein component of chylomicronsApo C-II
The major lipoprotein component of chylomicrons and remnant chylomicronsApo B-48
The major lipoprotein component of VLDL, IDL, LDL, Lp(a)Apo B-100
The major lipoprotein component of HDLApo A-I
The secondary lipoprotein component of chylomicrons and VLDLApo C-II
The secondary lipoprotein component of remnant chylomicrons and IDLApo E
The secondary lipoprotein component of Lp(a)Apo(a)
Has no secondary lipoprotein componentLDL
Has all other secondary lipoprotein except for Apo B'sHDL
The other non-protein constituents of chylomicrons and remnant chylomicronsVitamins A, D, E, and K
The other constituents of VLDL, IDL and LDLVitamin E
The other constituents includes LCAT, CETP and paroxonaseHDL
Hydrolysis of triacylglycerols are catalyzed by __________, mainly in muscle and adipose tissueEndothelial Lipoprotein Lipase (LPL)
Endothelial Lipoprotein Lipase (LPL) is an extracellular enzyme that is anchored to the capillary endothelium byHeparan Sulfate
Endothelial Lipoprotein Lipase (LPL) is activated by _______ which is present on circulating lipoproteinApo C-II
HDL donates apoproteins C-II and E which are given to nascent chylomicrons to formMature Chylomicrons
Nascent chylomicrons form from mature chylomicrons after HDL donatesApo C-II and E
Chylomicron remnants are taken up by remnant receptors through receptor-mediated endocytosis in the liver which will recognize __________ over the surface of chylomicronsApo E
The liver loads triacylglycerol, phospholipids and spingolipids onto __________ to be distributed throughout the bodyApo B-100
Triacylglycerol, phospholipids, _________ loaded onto Apo B-100VLDL
Protein that loads TAGs along with free and esterified cholesterol, phospholipids and vitamin E onto Apo B-100MTP
IDL does not contain _________ donating this protein back to HDLApo C-II
IDL donates _______ to HDL to become LDLApo E
LDL can be reabsorbed by the liver the receptor-mediated endocytosis byApo B-100 receptor (LDL receptor)
Competes with plasminogen for its substrate reducing the effectiveness of fibrinolysisLp(a)
Higher levels indicates an independent risk factor cardiovascular diseaseLp(a)
Servers as a storage for apoproteins for other apoprotein containing vesiclesHDL
Intracellular cholesterol is exported out of the cellABC Transporter
Cholesterol is esterfied by removing a fatty acid from phosphotitdylylcholine (lecithin)Lecithin Cholesterol Acyl Transferase (LCAT)
LCAT is activated byApo A-I
Transfers cholesterol ester for triacylglercerol to VLDL, IDL, LDLCholesterol Ester Transfer Protein (CETP)
HDL2 interacts with this liver receptor and off-loads all contents to the liver and becomes nascent HDLSR-B1 receptor
Hepatic lipase breaks down triacylglycerol leavingHDL3
Reverse cholesterol transport is carried out byHDL3
Hormone that has a positive effect on LPL, CETP LDL receptor, and hepatic lipaseT3/T4
Hormone that has a negative effect on oxidation of LDL reducing the risk atherosclerosisT3/T4

LDL Receptor

Question Answer
LDL receptor has ___ domains5 Domains
Domain 1Ligand-Binding Domain
Domain 2EGF Precursor Homology Domain
Domain 3O-linked Sugar Domain
Domain 4Membrane-Spanning Domain
Domain 5Cytoplasmic Domain
Ligand-Binding DomainDomain 1
EGF Precursor Homology DomainDomain 2
O-linked Sugar DomainDomain 3
Membrane-Spanning DomainDomain 4
Cytoplasmic DomainDomain 5

Fatty Acid Oxidation

Question Answer
Glucagon and epinephrine activatesHormone Sensitive Lipase
Acts on monoacylglycerol to release fatty acids and glycerolMonoacylglycerol Lipase
Glycerol enters intoGluconeogenesis
Fatty Acids enters into the mitochondria forOxidation
The carrier of fatty acids released from adipose tissue into the bloodAlbumin
Present over outer mitochondrial membrane, activates fatty acid by adding CoAAcyl CoA Synthetase
Also present over the outer mitochondrial membrane, enzyme that transfers long-chain fatty acyl groups from CoA to carnitine to make fatty acyl-carnitineCarnitine Acyl Transferase I
Transports the fatty acyl-carnitine across inner mitochondrial membrane and carnitine into the intermembrane spaceCarnitine Acylcarnitine Translocase
Enzyme that catalyzes the conversion of fatty-acyl-carnitine back to fatty acyl CoA and carnitineCarnitine Acyl Transferase II

Beta Oxidation

Question Answer
Fatty acyl CoA is cleaved to produce FADH + H+Acyl CoA Dehydrogenase
The first reaction of Beta Oxidation requires which vitaminRiboflavin
The third reaction of Beta Oxidation requires which vitaminNiacin
The fourth reaction of Beta Oxidation requires which vitaminPantothenic Acid
The number of ATPs produced by one round of Beta Oxidation17
The number of ATPs produced by the final round of Beta Oxidation of an even-number carbon Fatty Acid17 + 12
In odd-number Fatty Acid, the final round of Beta Oxidation produces acetyl CoA and _______Propionyl CoA

VLC Fatty Acid and Branched Chain Fatty Acid Oxidation

Question Answer
Degradation of ceruloplasmagin, VLCFA, BCFA and ferritin releasing components for plasminogen and bile acids occurs herePeroxisome
Branched chain fatty acids first undergo ________ because the beta carbon is occupied by a methyl groupAlpha Oxidation
This fatty acid under go alternating alpha-beta oxidation in the peroxisome until the C8 when it moves to the mitochondriaBranched


Question Answer
In well fed state, keeps acetyl CoA carboxylase active and increases malonyl CoAInsulin
During fasting and starvation: Causes lipolysis and increase in free fatty acids (acyl CoA) which inhibits acetyl CoA carboxylase and decreases malonyl CoAGlucagon
The concentration of __________ regulates whether fatty acid synthesis occurs or whether beta-oxidation occursMalonyl CoA

Ketogenesis and Ketolysis

Question Answer
Precursor for all three ketone bodiesAcetyl CoA
HMG CoA is lysed by HMG CoA lyase producing acetyl CoA and the first ketoneAcetoacetate
Acetoacetate will also undergo spontaneous decarboxylation to form volatile compound which is exhaledAcetone
Acetoacetate undergo oxidation to form beta (3)-hydroxybutyrate catalyzed by beta (3)-hydroxybutyrate dehydrogenase, in this process there is consumption ofNADH + H+
Formation of beta (3)-hydroxybutyrate is favored because of high levels ofNADH + H+
The rate limiting enzyme isBeta (3)-hydroxybutyrate Dehydrogenase
Utilization of ketone bodies by the tissues requires the activity of the enzymeThiophorase (CoA Transferase/Acetoacetate:Succinyl CoA CoA Transferase)
The liver cannot use ketone bodies because it does not containThiophorase (CoA Transferase/Acetoacetate:Succinyl CoA CoA Transferase)
Transfers CoA from succinyl CoA to activate acetoacetate to produce acetoacetyl CoAThiophorase (CoA Transferase/Acetoacetate:Succinyl CoA CoA Transferase)
Oxidation of beta (3)-hydroxybutyrate produces 1 NADH + H+ and 2 acetyl CoA yield27 - 1 ATP = 26 ATP

Glycerophopholipids and Sphingophopholipids

Question Answer
Synthesized in the ER by condensation of serine and palmitoyl CoACeramide
Ceramide plus a monosaccharideCerebroside
Ceramide plus a di-, tri- or tetrasacccharideGloboside
Ceramide plus a oligosaccharide plus N-acetyl neuraminic acid (NANA)Ganglioside
On electrogel, _____ moves the furthest on the gelGM3
On electrogel, _____ moves the least on the gelGM1


Question Answer
Pepsinogen is activated to its active form pepsin in the presence of acid (HCl) by this processAutocatalytic Activation
Trypsinogen is cleaved into its active form trypsin byEnteropetidase (Enterokinase)
Catalyzes the conversion of chymotrypsinogen to chymotrypsin, proelastase to elastase, and the procarboxypeptidases to the carboxypeptidasesTrypsin
Enteropetidase (Enterokinase) is secreted by _________ in the small intestineBrush Border Cells
Enzyme that acts on the carboxyl side of aromatic amino acids and positive-charged amino acidsPepsin
Endopeptidase enzyme that acts on carboxyl side of hydrophobic amino acidsChymotrysin
Exopeptidase enzyme that acts on carboxyl side of hydrophobic amino acidsCarboxypeptidase A
Exopeptidase enzyme that acts on carboxyl side of positive-charged amino acidsCarboxypeptidase B
Endopeptidase enzyme that acts on the carboxyl side of small-chain amino acidsElastase
Endopeptidase enzyme that acts on the carboxyl side of lysine and arginineTrypsin
In the intestine and kidney, amino acids can be transported across the cell membrane byγ-Glutamyl Cycle
Transfers amino group from aspartateAspartate Transaminase (AST)
Transfers amino group from alanineAlanine Transaminase (ALT)
All amino acids except for Lysine and Threonine can undergoTransamination Reaction
The conversion of an amino acid and an α-keto acid into another amino acid and α-keto acidTransamination Reaction
In a transamination reaction, the carbon skeleton for the second amino acid comes fromα-Keto Acid 1
In a transamination reaction, the amino group for the second amino acid comes fromAmino Acid 1
In a transamination reaction, the carbon skeleton for the second α-keto acid comes from Amino Acid 1
α-Ketoglutarate is converted into glutamate or the reverse if concentrations of glutamate is high in all Transamination Reaction
This coenzyme is required for transamination reactions to occurPyridoxal Phosphate (PLP)
Pyridoxal phosphate is derived fromPyridoxine (Vitamin B6)