Term
|
Definition
| This protein is used as a tag to identify proteins targeted for destruction |
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Term
|
Definition
| This is the primary proteolytic enzyme of the stomach |
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Term
|
Definition
| These enzymes transfer an alpha-amino group from amino acids to alpha-ketoglutarate |
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Term
|
Definition
| This enzyme catalyzes an oxidative deamination and can utilize either NAD+ or NADP+. |
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Term
|
Definition
| This is the type of intermediate that forms between PLP and an amino acid |
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Term
|
Definition
| This is the molecule that is formed from excess NH4+ by ureotelic organisms |
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Term
|
Definition
| This product results when aspartate is transaminated with -ketoglutarate |
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Term
|
Definition
| This methyl group donor is the product of the first step of methionine degradation |
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Term
|
Definition
| This class of enzymes cleave most aromatic rings in biological systems |
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Term
|
Definition
| This is the cofactor required by phenylalanine hydroxylase |
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Term
|
Definition
| The C-terminal glycine of ubiquitin is covalently linked to ________________ residues of the protein destined to be degraded. |
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Term
|
Definition
| Ubiquitin-tagged proteins are digested by the __________________. |
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Term
|
Definition
| In the transaminase reaction, pyridoxal phosphate is converted into __________________ when the first amino acid is converted into an -keto acid. |
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Term
|
Definition
| The hydrolysis of arginine by arginase produces ornithine and ______________. |
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Term
|
Definition
| Nitrogen is transported from muscle to liver in the form of ______________. |
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Term
| vitamine B6 or pyridoxine |
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Definition
| The vitamin that plays a key role in amino acid degradation is ________________. |
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Term
|
Definition
| Serine dehydratase catalyzes the conversion of serine into NH4+ and __________________. |
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Term
|
Definition
| In the degradation of amino acids, the amino nitrogens can eventually become the amino group of ___________________. |
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Term
|
Definition
| In the first step of the urea cycle, CO2 and NH4+ are converted into __________________. |
|
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Term
| branched chain alpha-keto acid dehydrogenase |
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Definition
| The genetic deficiency of the enzyme __________________________ results in a condition referred to as maple syrup urine disease |
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Term
|
Definition
|
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Term
|
Definition
| Which of the following is an allosteric activator of mammalian carbamoyl-phosphate synthetase? |
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Term
|
Definition
| The half-life of a cytosolic protein is primarily determined by the |
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Term
|
Definition
| In the urea cycle, the second nitrogen of urea enters the cycle in the form of which of the following metabolites? |
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|
Term
| a system for coenzyme biosynthesis |
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Definition
| The eukaryotic system for ubiquitination appears to have evolved from what prokaryotic precursor? |
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Term
|
Definition
| Which amino acids can be directly deaminated to produce NH4+? |
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Term
|
Definition
| In the urea cycle, free NH4+ is coupled with carboxyphosphate to form ______________. |
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Term
|
Definition
| Which amino acid(s) are metabolites in the urea cycle, but are not used as building blocks of proteins? |
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Term
|
Definition
| In the urea cycle, the carbon skeleton of aspartate is preserved as |
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Term
|
Definition
| Four of the five enzymes in the urea cycle are evolutionarily related to enzymes found in |
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Term
|
Definition
| Ammoniotelic organisms excrete excess nitrogen as |
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Term
|
Definition
| Uricotelic organisms release nitrogen as |
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|
Term
| acetyl-CoA and acetoacetate |
|
Definition
| Ketogenic amino acids are degraded to which of the following metabolites? |
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Term
|
Definition
| Which amino acids supply carbons for eventual entry into metabolism as succinyl CoA? |
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Term
|
Definition
| Which amino acid(s) is (are) converted to tyrosine in the degradative pathway? |
|
|
Term
| stable ring structure and monosaccharides formed under prebiotic conditions |
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Definition
| Which of the following are reasons that glucose is a common metabolic fuel used by living organisms? |
|
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Term
| trap glucose in the cell and destabilize glucose and facilitate the next series of metabolic steps |
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Definition
| What is the purpose of phosphorylating glucose in cytosol? |
|
|
Term
| glyceraldehyde-3-phosphate and dihydroxyacetone phosphate |
|
Definition
| What two 3-carbon molecules are generated by the cleavage of fructose-1,6-bisphosphate? |
|
|
Term
| binding of substrate induces cleft closing |
|
Definition
| What is a common mechanistic feature of kinases? |
|
|
Term
| reversible cleavage of F-1,6-BP to DHAP and GAP |
|
Definition
| What reaction is catalyzed by aldolase? |
|
|
Term
| oxidation by NAD+ and formation of acyl-phosphate |
|
Definition
| What is the function of glyceraldehyde 3-phosphate dehydrogenase? |
|
|
Term
| thioester allows the two-step reaction to be coupled so the second reaction, the energetically unfavorable phosphorylation, can proceed |
|
Definition
| What is the function of a thioester intermediate such as the one formed from GAP? |
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|
Term
| ATP synthesis when the phosphate donor is a substrate with high phosphoryl transfer potential |
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Definition
| What is substrate level phosphorylation? |
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Term
|
Definition
| What is the additional metabolite that is required for the conversion of 3-phosphoglycerate to 2-phosphoglycerate? |
|
|
Term
| ethanol, lactate, acetyl CoA |
|
Definition
| What are the primary metabolic fates of pyruvate? |
|
|
Term
| fructose is converted to fructose-6-phosphate |
|
Definition
| Fructose can enter glycolysis at two distinct points, depending on the tissue. How is fructose metabolized in adipose tissue? |
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Term
|
Definition
| Lactose intolerance is caused by a deficiency of |
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|
Term
| transcriptional control, reversible phosphorylation, allosteric control |
|
Definition
| How are the glycolytic enzymes regulated? |
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Term
|
Definition
| The primary raw materials for gluconeogenesis are |
|
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Term
|
Definition
| How many high-energy phosphate bonds are expended in gluconeogenesis? |
|
|
Term
| Krebs cycle and tricarboxylic acid cycle |
|
Definition
| The citric acid cycle is also known as the |
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Term
|
Definition
| What molecule initiates the citric acid cycle by reacting with oxaloacetate? |
|
|
Term
| pyruvate dehydrogenase complex |
|
Definition
| What enzyme(s) is (are) responsible for the following reaction? |
|
|
Term
| decarboxylation, oxidation, transfer to CoA |
|
Definition
| What are the steps involved (in order) in the conversion of pyruvate to acetyl CoA? |
|
|
Term
| thiamine, riboflavin, niacin, lipoic acid, and pantothenic acid |
|
Definition
| Which of the following vitamins are precursors to coenzymes that are necessary for the formation of acetyl CoA from pyruvate? |
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Term
|
Definition
| Which of the following functions as a “flexible swinging arm” when it transfers the reaction intermediate from one active site to the next? |
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Term
|
Definition
| Formation of citrate from acetyl CoA and oxaloacetate is a(n) _________ reaction |
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|
Term
| dehydration followed by hydration |
|
Definition
| What is/are the chemical change(s) involved in the conversion of citrate into isocitrate? |
|
|
Term
| conversion of succinyl CoA to succinate |
|
Definition
| In which reaction is GTP (or ATP) directly formed in the citric acid cycle? |
|
|
Term
| the conversion of succinate to fumarate |
|
Definition
| In which step of the citric acid cycle is FADH2 formed? |
|
|
Term
| elevated concentrations of NADH and ATP |
|
Definition
| Which of the following conditions will activate pyruvate dehydrogenase kinase which catalyzes the phorphorylation and inactivation of E1 in the pyruvate dehydrogenase complex? |
|
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Term
|
Definition
| Approximately how many ATP or GTP equivalents are produced during one turn of the citric acid cycle? |
|
|
Term
| isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, citrate synthase (in bacteria) |
|
Definition
| In addition to pyruvate dehydrogenase, what other enzymes are key regulatory sites in the citric acid cycle? |
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Term
|
Definition
| The glyoxylate cycle enables plants to survive using only |
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Term
|
Definition
| What type of gradient is critical to ATP formation by oxidative phosphorylation? |
|
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Term
|
Definition
| When glucose is totally oxidized to CO2 and H2O, how many ATP molecules are made by oxidative phosphorylation relative to the maximum yield? |
|
|
Term
| oligomycin blocks the proton transfer through Fo of ATP synthase and therefore blocks the phosphorylation of ADP to form ATP |
|
Definition
| What is the chemical effect of oligomycin on aerobic metabolism? |
|
|
Term
NADH -> complex I -> CoQ -> Complex III -> Cyt c -> complex IV -> O2
FADH2 -> complex II -> CoQ -> Complex III -> Cyt c -> complex IV -> O2 |
|
Definition
| Choose the correct path taken by a pair of electrons as it travels down the electron-transport chain. |
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Term
|
Definition
| Which of the following does not participate in, nor is a component of, the electron-transport chain? |
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Term
|
Definition
| In prokaryotes the site of ATP-synthesizing machinery is |
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|
Term
| transport of protons across the inner mitochondrial membrane from inside the matrix to the intermembrane space |
|
Definition
| Electron flow down the electron-transport chain leads to the |
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Term
|
Definition
| Coenzyme Q is also called |
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Term
|
Definition
| Which of the following does not pump protons? |
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Term
|
Definition
| In proteins these amino acid residues usually complex to the iron-sulfur clusters. |
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|
Term
| a protein that transfers electrons, and that also contains a heme prosthetic group |
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Definition
|
|
Term
|
Definition
| In the Rieske center, the iron-sulfur center is coordinated to the amino acid(s) _______ |
|
|
Term
| ADP3 + HPO42- + H+ <-> ATP4- + H2O |
|
Definition
| What is the reaction of ATP synthase? |
|
|
Term
|
Definition
| What is the net ATP obtained from one cytoplasmic NADH when it is reoxidized by the electron-transport chain using the glycerol 3-phosphate shuttle? |
|
|
Term
|
Definition
| In the malate-aspartate shuttle, electrons from NADH are transferred to ________, forming malate. |
|
|
Term
| liver and skeletal muscle |
|
Definition
| The major site(s) of glycogen storage is (are) |
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Term
|
Definition
| The key enzyme in glycogen degradation is |
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|
Term
| transferase and alpha-1,6-glucosidase |
|
Definition
| What enzyme(s) is (are) required to cleave alpha-1,6-glycosidic branches in glycogen? |
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Term
|
Definition
| Conversion of glucose 1-phosphate to glucose 6-phosphate is carried out by the enzyme |
|
|
Term
|
Definition
| What molecule must be excluded from the active site of glycogen phosphorylase? |
|
|
Term
| addition of a phosphate to a serine residue |
|
Definition
| How is phosphorylase b converted into phosphorylase a? |
|
|
Term
| active site is partially blocked |
|
Definition
| Why is the T state of glycogen phosphorylase less active? |
|
|
Term
| high ATP and high glucose 6-phosphate levels |
|
Definition
| What physiological conditions render phosphorylase b less active? |
|
|
Term
| for glucose export to other tissues when glucose levels are low |
|
Definition
| What is the function of liver glycogen degradation? |
|
|
Term
| Ca2+, cAMP activated PKA (Protein Kinase A) |
|
Definition
| Phosphorylase kinase is regulated by |
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Term
|
Definition
| Two critical hormones that signal for glycogen breakdown are |
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|
Term
|
Definition
| The key regulatory enzyme in glycogen synthesis is |
|
|
Term
| branching increases the solubility of glycogen and glycogen synthesis and degradation by increasing the potential sites of action |
|
Definition
| Why is glycogen branching important? |
|
|
Term
| blood-glucose levels increase leading to glycogen storage in the liver |
|
Definition
| Which of the following occur after a carbohydrate-rich meal? |
|
|
Term
| 80-120 mg/100 mL (4.4-6.7 mM) |
|
Definition
| What is the normal glucose concentration in blood? |
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Term
|
Definition
| ATP is called the energy currency. The currency of reducing power is |
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Term
|
Definition
| What is the source of carbons for the Calvin cycle? |
|
|
Term
| radioactive tracer experiments using 14CO2 |
|
Definition
| What experiments led to the proof that carbon dioxide was incorporated into 3-phosphoglycerate? |
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Term
|
Definition
| In the Calvin cycle, 3-phosphoglycerate is converted into which hexose phosphate? |
|
|
Term
| ribose 5-phosphate and xyulose 5-phosphate |
|
Definition
| Which sugar(s) is (are) converted into ribulose 5-phosphate by a single enzymatic step? |
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Term
|
Definition
| Which form of thioredoxin activates certain Calvin cycle enzymes? |
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Term
|
Definition
| Which coenzyme is required by glyceraldehyde 3-phosphate dehydrogenase in chloroplasts to convert 3-phosphoglycerate into glyceraldehyde-3-phosphate? |
|
|
Term
| at high temperatures, the oxygenase activity of rubisco is high |
|
Definition
| The C4 pathway is necessary in tropical plants because |
|
|
Term
| 30 molecules of ATP are used per hexose molecule made |
|
Definition
| What is the energy cost of the C4 pathway? |
|
|
Term
| generate NADPH and synthesize 5-carbon sugars |
|
Definition
| The purpose of the pentose phosphate pathway is to |
|
|
Term
| a thousand times lower than |
|
Definition
The KM of glucose 6-phosphate dehydrogenase for NADP+ is _____________ the KM for
NAD+ |
|
|
Term
| C5 + C6 <-transketolase-> C2 + C9 |
|
Definition
| Which of the following reactions is not part of the pentose phosphate pathway? |
|
|
Term
|
Definition
| What is the net reaction of the transketolase and transaldolase steps? |
|
|
Term
|
Definition
Which of the following tissues do not contain the enzymes for an active pentose-phosphate
pathway? |
|
|
Term
|
Definition
Which cofactor is required by glutathione reductase to aid in the reduction of oxidized
glutathione by NADPH? |
|
|
Term
| phospholipids and glycolipids |
|
Definition
| Fatty acids are the building blocks of |
|
|
Term
| anhydrous and highly reduced |
|
Definition
| Why are triacylglycerols an excellent design for energy stores? |
|
|
Term
|
Definition
| Enzymes that digest the triacylglycerols into free fatty acids and monoacylglycerol are called |
|
|
Term
|
Definition
| The hormone __________ induces lipolysis, whereas the hormone __________ inhibits the process. |
|
|
Term
| ATP-dependent activation of fatty acids using CoA |
|
Definition
| The function of the enzyme acyl CoA synthetase is |
|
|
Term
|
Definition
| Coenzyme(s) involved in the degradation of saturated fatty acyl CoA include(s) |
|
|
Term
| 7 Acetyl-CoA + 6 FADH2 + 6 NADH + 6 H+ |
|
Definition
| The beta oxidation of myristyl-CoA (C-14:0) yields |
|
|
Term
|
Definition
| How many rounds of beta oxidation would be required for a 16-C fatty acyl chain to be degraded to acetyl-CoA? |
|
|
Term
| intramolecular rearrangements, methylations, reduction of ribonucleotides to deoxyribonucleotides |
|
Definition
| What types of reactions do cobalamin enzymes catalyze? |
|
|
Term
| initial dehydrogenation reaction is different in that electrons are transferred to O2 to yield H2O2 |
|
Definition
| How does beta oxidation differ in peroxisomes? |
|
|
Term
| heart muscle, renal cortex |
|
Definition
| What organs or tissues prefer to use ketone bodies such as acetoacetate as a fuel energy source instead of glucose? |
|
|
Term
|
Definition
| What is the committed step in fatty acid synthesis? |
|
|
Term
| palmitate + 7 CO2 + 14 NADP+ + 8 CoA + 6 H2O |
|
Definition
Complete this reaction:
Acetyl CoA + 7 malonyl CoA + 14 NADPH + 20 H+ -> |
|
|
Term
| enzyme is switched off by phosphorylation and activated by dephosphorylation |
|
Definition
| How is acetyl carboxylase globally regulated? |
|
|
Term
| by elongation reactions catalyzed by enzymes on the endoplasmic reticulum |
|
Definition
| How are fatty acids larger than 16 carbons formed? |
|
|
Term
|
Definition
| Which of the following is the common precursor for both the phosphatidyl inositols and triacylglycerols? |
|
|
Term
| glycerol 3-phosphate and two fatty acyl-CoA’s |
|
Definition
| Phosphatidate is formed from |
|
|
Term
| stearic acid; arachidonic acid |
|
Definition
| In phosphatidyl inositol, __________ and _________ usually occupy the C-1 position and the C-2 position, respectively |
|
|
Term
|
Definition
| The highest concentration of sphingolipids is found in the |
|
|
Term
|
Definition
| The starting materials necessary to synthesize sphingosine are |
|
|
Term
|
Definition
| Which of the following is the major component of low-density lipoproteins? |
|
|
Term
| dipalmitoyl phosphatidyl choline |
|
Definition
| Respiratory distress syndrome is caused by a failure in the biosynthetic pathway of |
|
|
Term
|
Definition
| Tay Sachs disease is caused by an inability to degrade |
|
|
Term
|
Definition
| HMG CoA is synthesized from acetyl CoA and |
|
|
Term
| 3-hydroxy-3-methylglutaryl CoA reductase |
|
Definition
| Feedback regulation of cholesterol synthesis is mainly controlled at the step catalyzed by the enzyme |
|
|
Term
| solubilize hydrophobic lipids and contain cell-targeting signals |
|
Definition
| The role of lipoprotein particles is to |
|
|
Term
|
Definition
| The major carrier(s) of dietary fat from the intestine is (are) |
|
|
Term
|
Definition
| The LDL receptors on the plasma membrane are localized in coated pits that contain the receptors of which of the following proteins? |
|
|
Term
|
Definition
| Which of the following combines with cholic acid to form a major bile salt? |
|
|
Term
|
Definition
| Hydroxylation of cholesterol by cytochrome P450 requires |
|
|
Term
pyruvate -> acetyl-CoA + CO2
alpha-ketoglutarate -> succinyl-CoA + CO2 |
|
Definition
| Excess alcohol consumption can lead to Wernicke-Korsaff syndrome due to the lack of the vitamin thiamine. Which of the following metabolic conversions cannot occur in the absence of thiamine? |
|
|
Term
|
Definition
| The major electron donor in reductive biosynthesis is |
|
|
Term
|
Definition
| An important regulatory enzyme in glycolysis is |
|
|
Term
| degrading glucose to provide ATP and providing carbon skeletons for biosynthesis |
|
Definition
| The function(s) of glycolysis include(s) |
|
|
Term
| rate of the citric acid cycle matches the need for ATP |
|
Definition
| What does respiratory control ensure? |
|
|
Term
| glycogen, pyruvate, ribose 5-phosphate |
|
Definition
| The most common end product(s) of glucose metabolism include(s) |
|
|
Term
| G-6-P, alanine, pyruvate, acetoacetate, fatty acids |
|
Definition
| Acetyl-CoA is derived from |
|
|
Term
transamination to alanine,
carboxylation to oxaloacetate,
reduction to lactate |
|
Definition
| What are some of the metabolic fates of pyruvate? |
|
|
Term
|
Definition
| Which of the following is the fuel used by the brain during starvation? |
|
|
Term
|
Definition
| In a typical human male, what is the energy content (in kcal) of triacylglycerols stored in adipose tissue? |
|
|
Term
|
Definition
| The ___________ is an important site of gluconeogenesis during starvation |
|
|
Term
|
Definition
| What is the primary source of energy used by the liver for its own energy requirements? |
|
|
Term
|
Definition
| Maintenance of a constant blood-glucose level is called |
|
|
Term
|
Definition
| Insulin signals the ______ state, and glucagon signals the _______ state |
|
|
Term
|
Definition
| Which of the following molecules or metabolic conversions provides the maximum rate of ATP production (mmol/sec) for muscle contraction? |
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|
