Question Clues - Biochemistry Flashcards
What is the most common extracellular buffer?
Bicarbonate
What is the isoelectric point?
The pH at which there is no net charge
What is the rate-limiting enzyme in Glycolysis?
Phosphofrutokinase-1 (PFK-1)
What is the rate-limiting enzyme in Gluconeogenesis?
Fructose-1,6-Bisphosphatase
What is the rate-limiting enzyme in the HMP shunt?
Glucose-6-Phosphate Dehydrogenase (G-6-PD)
What is the rate limiting enzyme in glycogenesis?
Glycogen Synthase. Occurs in the Cytolasm of Liver and Muscle
What is the rate-limiting enzyme in Glycogenolysis?
Glycogen Phosphorylase. Occurs in the Cytoplasm of Liver and Muscle
What is the rate-limiting enzyme in FA synthesis?
Acetyl-CoA Carboxylase (ACC)
What is the rate-limiting enzyme in Beta-Oxidation?
Carnitine ACyltransferase-1 (CAT-1)
What is the rate-limiting enzyme in Cholesterol synthesis?
HMG CoA Reductase
What is the rate-limiting enzyme in Ketogenesis?
HMG CoA Synthase
What is the rate-limiting in Purine Synthesis?
Glutamine - phosphoribosyl pyrophosphate (PRPP) Amidotransferase
What is the rate-limiting enzyme in Pyrimidine synthesis?
Carbamoyl Phosphate Synthetase - 2 (CPS - 2)
What is the rate-limiting enzyme in TCA cycle?
Isocitrate dehydrogenase
What is the rate-limiting enzyme in Urea cycle?
Carbamoyl Phosphate Synthetase - 1 (CPS-1)
What is the rate-limiting enzyme in Heme synthesis?
delta-ALA Synthase
What are the catabolic pathways that create energy? (Occur in the Mitochondria)
Acetyl-CoA production, Beta-Oxidation, citric acid cycle, Ketogenesis, Oxidative Phosphorylation (ETC)
What are the anabloic pathways that store energy? (Occur in the Cytoplasm)
Fatty acid synthesis, Glycolysis, HMP Shunt, translation
What are the anabolic + catabolic pathways? (occurs in both cytoplasm and mitochondria)
HUG - Heme synthesis, Urea Cycle, Gluconeogenesis
What does an Isomerase do?
Creates an isomer
What does an Epimerase do?
Creates an epimer, which differs around one chiral carbon
What does a Mutase do?
Relocates a functional group within a molecule (intrachain)
What does a Transferase do?
Relocates a functional group from one molecule to another (interchain)
What does a Kinase do?
Adds Phosphate group to substrate using ATP
What does a phosphorylase do?
Adds inorganic phosphate to substrate. No ATP used
What does a Carboxylase do?
Transfers CO2 groups with the help of Biotin (B7)
What does a synthase do?
Consumers two substrates
What does a Synthetase do?
Comsumes two substrates, uses ATP
What does a phosphatase do?
Removes phosphate from substrate
What does a hydroxylase do?
Adds-Oh group onto substrate
What does a lyase do?
Cuts C-C bonds with ATP
What does a dehydrogenase do?
Catalyzes oxidation-reduction reactions (gaining or losing an electron)
What does thio do?
Breaks S bonds
What is diffusion?
From high to low concentration. No ATP used
What is Active Transport?
Goes against concentration gradient. Requires ATP
What is zero-order kinetics?
Metabolism independent of concentration (rate of elimination is constant)
What is 1st-order kinetics?
Constant drug percentage metabolism over time depends on drug concentration (rate of elimination is directly proportional to drug concentration)
What is efficacy?
Vmax
What is potency?
Amount of drug needed to produce effect (lower w/ comp antagonist)
What affects potency?
Km (EC50)
What is Kd?
Concentration of drug that binds 50% of receptors
What is the Ec50?
Concentration of drug that produces 50% of maximal response.
What is competitive inhibition?
Fights for active site, no change in Vmax, potency decreases
What is Non-competitive inhibition?
Binds a regulatory site, no change in Km, Efficacy decreases, decreased Vmax
What is the Peak level?
4 hours after does (too high - decrease dose_
What is the Trough level?
2 hours before next dose (too high - give less often)
What is the T1/2?
Half-life, the time it takes the body to use half of the drug ingested.
What is von Gierke?
G-6 Phosphatase deficiency, severe fasting hypoglycemia, hepatomegaly, increasd lactase and uric acid levels
What is Pompe’s?
Lysosomal alpha-1,4-glucosidase deficiency. Usually die early/young due to heart failure. Think Pump with Pompe’s
What is Cori’s?
Debranching, alpha-1,6-glucosidase enzyme deficiency, short branches of glycogen, milder form of von Gierke with normal lactate levels, limit-dextrin’s accumulate
What is Anderson’s?
Branching enzyme deficiency, long chains of glycogen
What is McArdle’s?
Myophosphorylase deficiency, (skeletal muscle Glycogen Phosphorylase), muscle cramps with exercise, increased Glycogen in muscle only, blood glucose NL, second wind phenomenon
What is essential fructosuria?
Fructokinase deficiency, excrete fructose in blood/urine (still have hexokinase)
What is Fructosemia?
“Fructose intolerance” (Aldolase B deficiency) Kidney and liver damage, occurs in infants after introduction of fruits, honey and juices
What does a Galactokinase deficiency cause?
Cataracts
What does Galactosemia cause?
Cataracts, mental retardation, liver damage
What does the Citrate shuttle do?
FA transport out of the mitochondria
What lysosomal diseases have a cherry-red macula?
Tay-Sachs, Niemann-Pick
