Term
| What is the major energy reserve for the body? |
|
Definition
| Esterified fatty acids, in the form of triacylglycerols stored in adipose cells |
|
|
Term
| Lipases can __________ triacylglycerols, releasing one fatty acid at a time to yield _______________ and __________. |
|
Definition
| hydrolyze;diacylglycerols & glycerol |
|
|
Term
| Glycerol can be converted to the glycolysis intermediate dihydroxyacetone phosphate (DHAP), by reactions catalyzed by: |
|
Definition
1 Glycerol Kinase
2 Glycerol Phosphate Dehydrogenase. |
|
|
Term
| Fatty acids must be converted to ___________ before they can undergo oxidative degradation or be utilized for synthesis of complex lipids. |
|
Definition
|
|
Term
| What converts fatty acids to CoA? |
|
Definition
| Acyl-CoA Synthases in the ER and outer mitochondria |
|
|
Term
| Converting fatty acids to coenzyme A occurs in 2 steps and is __________ dependent. |
|
Definition
|
|
Term
| There are different acyl-CoA synthanses for fatty acids with different what? |
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Definition
|
|
Term
| Where are double bonds in a FA chain nearly always? |
|
Definition
|
|
Term
| Double bonds are always spaced at how many intervals? |
|
Definition
|
|
Term
| Carbon 2 is what carbon? alpha or beta |
|
Definition
|
|
Term
| Carbon one is what carbon? one or alpha? |
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Definition
|
|
Term
| Fatty acid synthesis occurs primarily where? |
|
Definition
| the liver and lactating mammary glands and to a lesser extend adipose tissue |
|
|
Term
| Mitochondrial acetyl CoA is produced by what? |
|
Definition
| oxidation of pyruvate an catabolism of FA, ketone bodies, and certain AA |
|
|
Term
| What portion of acetyl CoA can enter into the cytosol? |
|
Definition
|
|
Term
| How many phosphate bonds are cleaved from ATP when converting FA to aceyl CoA? |
|
Definition
|
|
Term
| The Aceyl CoA product contains one _________ linkage (S-CoA, sulfur and aceyl group) |
|
Definition
|
|
Term
| Converting FA to aceyl CoA is endergonic/exergonic? |
|
Definition
|
|
Term
| FA are degraded inside/outside the mitochondrial matrix via the __________ pathway. |
|
Definition
|
|
Term
| Many of the constituent enzymes are ________ proteins located inside the mitochondrial matrix |
|
Definition
|
|
Term
| Enzymes specific for very long chain fatty acids are associated with what? |
|
Definition
| inner mitochondrial membrane |
|
|
Term
| ___________ formed ___________ can pass through the outer mitochondrial membrane but cannot penetrate the inner membrane |
|
Definition
| Fatty acyl-CoA;outside in cytosol |
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|
Term
| ___________________ are the most abundant dietary lipids. They are the form in which we store reduced carbon for energy. |
|
Definition
| Triacylglycerols (triglycerides) |
|
|
Term
| Most naturally occurring fatty acids have an ________ number of carbon atoms |
|
Definition
|
|
Term
| Lipases can ________ triacylglycerols, releasing one fatty acid at a time to yield ____________ and __________. |
|
Definition
| hydrolyze;diacylglycerols & glycerol |
|
|
Term
| What catalyzes the Aceyl CoA synthase when cleaving 2 phosphate bonds from ATP? |
|
Definition
|
|
Term
| Transfer of the fatty acid across the mitochondrial inner membrane involves _____________. |
|
Definition
| carnitine (referred to as the carnitine shuttle) |
|
|
Term
| What is the name given to the three enzymes that make up the carnitine shuttle? |
|
Definition
| Carnitine Palmitoyl Transferases |
|
|
Term
| Where is the first enzyme, CPT-I, found? |
|
Definition
| outer mitochondrial membrane |
|
|
Term
|
Definition
| acylcarnitine, and regenerates free CoA |
|
|
Term
| What does the second enzyme, carnitine-acylcarnitine translocase, do? |
|
Definition
| Transports acylcarnitine into mitochondrial matrix in exchange for free carnitine |
|
|
Term
| What does the third enzyme, carnitine palmitoyltransferase II (CPT-II), do? |
|
Definition
| catalyzes the transfer of the acyl group from carnitine to CoA in the mitochondrial matrix, thus regenerating free carnitine. |
|
|
Term
| Where is the third enzyme, CPT-II, found? |
|
Definition
| inner mitochondrial membrane |
|
|
Term
| Carnitine Palmitoyl Transferase I, an enzyme on the _______ surface of the _______ mitochondrial membrane, transfers a fatty acid from _____ to the OH on __________. |
|
Definition
| cytosolic;outer; CoA; carnitine |
|
|
Term
| What is enzyme 2, carnitine-acylcarnitine translocase, also refered to as? |
|
Definition
|
|
Term
| What step does carnitine leave in? |
|
Definition
|
|
Term
| What happens to the fatty acid in step three? |
|
Definition
| The fatty acid is now esterified (an OH is replaced by an O) to CoA in the matrix |
|
|
Term
| Control of fatty acid oxidation is exerted mainly at the step of ____________? |
|
Definition
| fatty acid entry into mitochondria (& lipase) |
|
|
Term
| What indicates FA synthesis? |
|
Definition
|
|
Term
| Malonyl-CoA (which is also a precursor for fatty acid synthesis) inhibits _______________. |
|
Definition
| Carnitine Palmitoyl Transferase I. |
|
|
Term
| The inhibition of CPT-I by malonyl CoA prevents what? |
|
Definition
| The entry of long chain acyl groups into the mitochondrial matrix. |
|
|
Term
| Malonyl-CoA is produced from __________ by the enzyme _____________. |
|
Definition
| acetyl-CoA; Acetyl-CoA carboxylase |
|
|
Term
| AMP-activated kinase, is allosterically activated by ______. |
|
Definition
|
|
Term
| Acetyl-CoA carboxylase is inhibited when _________ by _____________, leading to __________ malonyl-CoA. |
|
Definition
| phosphorylated;AMP-activated kinase; decreased |
|
|
Term
| The decrease in malonyl-CoA concentration leads to __________ activity of Carnitine Palmitoyl Transferase I. |
|
Definition
|
|
Term
| Increased ______________ then generates acetyl-CoA, for entry into__________ with associated ATP production |
|
Definition
| fatty acid oxidation; Krebs cycle |
|
|
Term
| The pathway for _________ of fatty acids is referred to as the ____________ pathway, because oxidation occurs at the_____ carbon (C-__). |
|
Definition
| catabolism;beta oxidation pathway; beta carbon; C-3 |
|
|
Term
| The beta oxidation breaks down fats into: |
|
Definition
Acetyl coenzyme A --> Kreb Cycle
FADH2 --> Oxidative Phosphorylation
NADH--> Oxidative Phosphorylation |
|
|
Term
Breaks off ____ carbons at a time to ________
Remaining triacylglyceride chain ___________. |
|
Definition
| two; acetyl CoA; goes another round |
|
|
Term
| only regulatory mechanism is hormone sensitive _________ in _______ tissue. (glucagon phosphorylates & thus ________ lipase) |
|
Definition
| lipase; adipose tissue; activates |
|
|
Term
| Step 1 of beta oxidation- __________ catalyzes oxidation of the fatty acid of acyl-CoA to produce a _________ between carbon atoms ___ and ___ . |
|
Definition
| Acyl CoA dehydrogenase; double bond; C2 and C3 |
|
|
Term
| Fatty acid chains shorter than ___ carbons can enter the mitochondrial matrix without carnitine shutte or CPT system. |
|
Definition
|
|
Term
| Step one of beta oxidation has ___ rxns which result in _________ of fatty acid chains by ___ carbons. |
|
Definition
|
|
Term
| The first rxn in beta oxid. is an ________ process that produces __________. |
|
Definition
|
|
Term
| The second rxn in beta oxid. is a __________ step. |
|
Definition
|
|
Term
| The third rxn in beta oxid. is a __________ step that produces _________. |
|
Definition
|
|
Term
| The fourth rxn in beta oxid. involves a _________ __________ that releases one molecule of _________. |
|
Definition
| thiolytic cleavage; Acetyl CoA |
|
|
Term
| The final thiolytic cleavage produces _____ acetyl groups. |
|
Definition
|
|
Term
| Acetyl CoA is a _____________ allosteric effector of ___________ ________________, thus linking fatty acid oxidation and ___________. |
|
Definition
| postive; pyruvate carboxylase; gluconeogenesis |
|
|
Term
| Step Two of Beta Oxid- __________ catalyzes hydration of the ______________ produced in the 1st step, yielding ____________ (adds water, forms ß-hydroxy product). |
|
Definition
| Enoyl-CoA Hydratase; double bond;L-hydroxyacyl-Coenzyme A |
|
|
Term
| what is the most common inborn error of metabolism? |
|
Definition
| MCAD deficiency, Medium chain fatty acyl CoA dehydrogenase deficiency |
|
|
Term
|
Definition
| decrease in fatty acid oxidation and severe hypoglycemia (because the tissues cannot obtain full energetic benefit from fatty acids and must rely on glucose |
|
|
Term
| Step 3. _____________ catalyzes oxidation of the hydroxyl in the beta position (C3) to a ______. ____ is the electron acceptor (oxidation produces a _________ and _________). |
|
Definition
| Hydroxyacyl-CoA Dehydrogenase; ketone; NAD+; ketone and NADH |
|
|
Term
| Step 4 of beta oxidation- __________ catalyzes thiolytic (a thiol is SH) cleavage. This produces __________ (goes to Krebs cycle) & a shortened fatty acyl-CoA (less 2 C) that can go another round of beta oxidation. |
|
Definition
| b-Ketothiolase ;acetyl-CoA; |
|
|
Term
| If, as is usually the case, the fatty acid contains an even number of C atoms, in the final reaction cycle ___________ is converted to __________ molecules. |
|
Definition
| butyryl-CoA; 2 acetyl coA molecules |
|
|
Term
| What is the total ATP produces from beta oxidation? |
|
Definition
|
|
Term
| ATP production from acetyl coA in krebs equals? |
|
Definition
|
|
Term
| ATP production from FADH2 and NADH in beta oxidation equals? |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Additional enzymes are needed to catabolize fatty acids with an _____ number of C atoms or with _______ ________. |
|
Definition
|
|
Term
| The final round of b-oxidation of a fatty acid with an odd number of C atoms yields acetyl-CoA & ____________. |
|
Definition
|
|
Term
| Propionyl-CoA is converted to the Krebs cycle intermediate ____________. |
|
Definition
|
|
Term
| b-Oxidation of very long-chain fatty acids (20-26 C) Occurs in the ______________. |
|
Definition
|
|
Term
| Similar to b-Oxidation except that _________ is produced |
|
Definition
|
|
Term
| ________ then degrades H2O2 |
|
Definition
|
|
Term
| Beta oxid. of long chain fatty acids produce no ____________, _________, or __________. |
|
Definition
|
|
Term
| Once reduced in length within the peroxisomes, FA can shift to the mitochondria to be catabolized all the way to _____. |
|
Definition
|
|
Term
| ___________ does transfer of fatty acids in & out of peroxisomes |
|
Definition
|
|
Term
| During fasting or carbohydrate starvation, _______________ is depleted in liver due to _____________. |
|
Definition
| oxaloacetate; gluconeogenesis |
|
|
Term
| Lack of ___________ due to gluconeogenesis, impedes entry of _________ into Krebs cycle. |
|
Definition
|
|
Term
| Acetyl-CoA in liver mitochondria is converted then to the ____________ and _________. |
|
Definition
| ketone bodies acetoacetate & b-hydroxybutyrate |
|
|
Term
| The final step of the b-oxidation pathway runs backwards and uses the enzyme ____________. |
|
Definition
|
|
Term
| In the first step of ketone synthase (the end of beta oxid) ___________ catalyzes condensation of acetyl CoA + acetoacetyl CoA to form _________. |
|
Definition
|
|
Term
| The second step of ketone synthase (the end of beta oxid) __________ cleaves HMG-CoA to yield __________ and __________. |
|
Definition
| HMG-CoA lyase;acetyl CoA & the ketone acetoacetate. |
|
|
Term
| The third step of ketone synthase _____________ then reduces acetoacetate to the ketone b-hydroxybutyrate. |
|
Definition
| b-hydroxybutyrate dehydrogenase ; |
|
|
Term
| Acetoacetate also spontaneously reduces to _______. |
|
Definition
|
|
Term
| _________ can be converted back to acetyl-CoA for catabolism in Krebs cycle. Brain can use ______ for fuel. |
|
Definition
| ketone bodies; ketone bodies |
|
|
Term
| Ketones that build up in the body for a long time lead to serious illness and coma b/c of decreased pH. also known as ________ _______. |
|
Definition
|
|
Term
| What gives breath a fruity odor? |
|
Definition
|
|
Term
| What are the three ketones? |
|
Definition
| acetoacetate, 3 hydroxybutyrate, acetone |
|
|
Term
| What is the rate limiting step in the synthesis of ketone bodies? it is found only in the liver. |
|
Definition
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