Term
| Energenic barrier that prevents glycolysis from simply running in reverse to synthesize glucose (gluconeogenesis) |
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Definition
- highly endergonic in reverse under cell conditions
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Term
| Energenic cost of overcoming endergonic barrier in gluconeogenesis |
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Definition
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Term
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Definition
- readily converted into pyruvate
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Term
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Definition
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Term
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Definition
- required for pyruvate carboxylase activity
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Term
| Phosphoenolpyruvate carboxykinase |
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Definition
- generates a high-phosphoryl-transfer-potential compound
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Term
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Definition
- readily converted into DHAP
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Term
| fructose 1,6-bisphosphatase |
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Definition
- gluconeogenic counterpart of PFK
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Term
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Definition
- found predominantly in the liver
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Term
| Rxns of glycolysis are not reversible under intracellular conditions |
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Definition
- formation of pyruvate and ATP by pyruvate kinase
- formation of fructose 1,6-BP by PFK
- hexokinase catalyzing formation of glucose 6-phosphate
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Term
| bypasses formation of pyruvate and ATP by pyruvate kinase in gluconeogenesis |
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Definition
- formation of PEP from oxaloacetate & GTP by PEP carboxykinase
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Term
| bypasses formation of F 1,6-BP from fructose 6-phosphate by PFK |
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Definition
| catalyzing of conversion of fructose 1,6-BP to fructose 6-phosphate by fructose 1,6 Bisphosphatase |
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Term
| bypasses hexokinase catalyzed formation of glucose 6-phosphate |
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Definition
- glucose 6-phosphatase (only in liver)
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Term
| gluconeogenesis takes place during intense exercise, why synthesize gluscose at the same time it is needed to generate energy |
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Definition
- example of interorgan cooperation, muscle creates lactate and is released into the blood stream, taken up by liver and converted to glucose in gluconeogenesis and released back into blood to be taken up by muscles for energy
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Term
| liver is primarily gluconeogenic, muscle is glycolytic, why the division of labor |
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Definition
- lactic acid is a stong acid, therefore can't accumulate in the blood or muscle, liver removes it and transforms it into glucose and releases it into blood or stores it as glycogen for later use
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Term
| effect on ability to use glucose as energy if mutation inactivated glucose 6-phosphatase in liver |
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Definition
- glucose produced would not be able to be released into blood, therefore tissue would only have dietary glucose to rely on
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Term
| why is the lack of glucose 6-phosphate activity good in brain and muscle |
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Definition
- glucose is the primary source of energy for these tissues and the enzyme would cause the cells to release thier glucose
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Term
| Number of NTP molecules to synthesize one molecule of glucose from two molecules of pyruvate |
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Definition
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Term
| Number of NADH molecules to synthesize one molecule of glucose from two molecules of pyruvate |
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Definition
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Term
| reciprocal regulation of gluconeogenesis & glycolysis; gluconeogenesis side |
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Definition
- enzymes in both cycles act as control points
- activated by: citrate, acetyl CoA
- inhibited by : F 2,6-BP, ADP, AMP
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Term
| reciprocal regulation of gluconeogenesis & glycolysis; glycolysis side |
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Definition
- enzymes in both cylcles act as control points
- activated by: F 2,6-BP, AMP, F 1,6-PB
- inhibited by: ATP, alanine, citrate, protons
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Term
| which conditions increase activity of the glycolytic pathway |
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Definition
- increase in AMP
- increase in F 2,6-BP
- increase in insulin
- fed
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Term
| which conditions increase the activity of gluconeogenic pathway |
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Definition
- increase in ATP
- increase in citrate
- increase in acetyl CoA
- increase in glucagon
- fasting
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Term
| predict effects on pace of glycolysis for loss of allosteric site for ATP in PFK |
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Definition
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Term
| predict effects on pace of glycolysis for loss of citrate binding site on PFK |
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Definition
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Term
| predict effects on pace of glycolysis for loss of phosphotase domain controling level of F 2,6-BP |
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Definition
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Term
| predict effects on pace of glycolysis for loss of binding site for F 1,6-BP in pyruvate kinase |
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Definition
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Term
| factor the additional high-phophoryl-transfer compounds alter the equilibrium constant of gluconeogenesis |
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Definition
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Term
| rxn that links glycolysis and the citric acid cycle |
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Definition
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Term
| enzyme that catalyzes the rxn that links glycolysis to the citric acid cycle |
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Definition
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Term
| 2 fates that the conversion of a pyruvate into acetyl CoA commits the carbon atoms to |
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Definition
- oxidation into citric acid cycle
- incorporation into lipids
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Term
| fatty acid breakdown generates large amounts of acetyl CoA, the effect it has on puruvate dehydrogenase complex activity |
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Definition
- it will inhibit the activity of the complex
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Term
| fatty acid breakdown generates large amounts of acetyl CoA, the effect it has on glycolytic activity |
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Definition
| activity will be slowed b/c acetyl CoA is being derived from another source |
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Term
| why no O2 is needed for the CAC although it is a part of aerobic respiration |
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Definition
-
CAC depends on supply of NAD+, which is generated from rxn of NADH w/ O2 ,no oxygen to accept e-, CAC will cease to operate
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Term
| energy source that drives the formation of citrate |
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Definition
- hydrolysis of the thioester bond that is present on acetyl CoA. It is converted to citryl CoA and then hydrolyzed converting to citrate
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Term
| value of ΔG0l for complete oxidation of acetyl unit of acetyl CoA in CAC |
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Definition
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Term
| idea that CAC can be considered a supramolecular enzyme |
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Definition
- a catalyst facilitates a chemical rxn w/out itself being permenantly altered, CAC operates in that oxaloacetate binds an acetyl group leading to 2 oxidative decarboxylations of 2 C and is regenerated at the end of the cycle
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Term
| change in the CAC intermediates after addition of inhibitor malonate |
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Definition
- succinate, α-ketoglutarate, and other up stream intermediates will increase in concentration
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Term
| why malonate is not a substrate for succinate dehydrogenase |
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Definition
- only has one methylene group, where as succinate has 2 methylene groups and 2 are required for dehydrogenation
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Term
| rxn in CAC that results in formation of 1 ATP |
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Definition
- rxn catalyzed by succinyl CoA synthetase
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Term
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Definition
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Term
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Definition
- donates e- to an acceptor
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Term
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Definition
- an ATP-generating process in which an inorganic compound serves as the final e- acceptor
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Term
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Definition
- measure of the tendency to accept or donate e-
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Term
| Electron Transport Chain (ETC) |
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Definition
- e- flow from NADH & FADH2 to O2
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Term
| flavin mononucleotide (FMN) |
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Definition
- accepts e- from NADH in complex I
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Term
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Definition
- facilitates e- from FMN to CoQ
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Term
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Definition
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Term
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Definition
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Term
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Definition
| funnels e- from a 2 e- carrier to a 1 e- carrier |
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Term
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Definition
- converts reactive oxygen species into hydrogen peroxide
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Term
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Definition
- converts hydrogen peroxide into oxygen and water
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Term
| why CoQ is an effective mobile electron carrier in the ETC |
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Definition
- soluble in a hydrophobic environment d/t isoprene units & contains 2 O atoms that can reversibly bind 2 e- & 2 H+ to transition b/t quinone and quinol
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Term
| reactive oxygen species (ROS) |
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Definition
-
hydroxyl radical (-OH.)
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hydrogen peroxide (H2O2)
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superoxide ion (O2-.)
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peroxide (O2-)
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Term
| why ROS are dangerous to cells |
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Definition
- react with macromolecules such as proteins, nucleotides, & membranes, disrupting cell structure & function
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Term
| CAC enzyme the is also a part of ETC |
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Definition
- succinate dehydrongenase (complex II, FADH2)
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Term
| how is descrepancy b/t energy requirements and resources reconciled |
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Definition
- ATP is regenerated by oxidative phosphorylation and other ATP generating processes
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Term
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Definition
- converts the proton-motive force into ATP
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Term
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Definition
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Term
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Definition
- generates the proton gradient
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Term
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Definition
- cytoplasmic NADH to mitochondrial FADH2
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Term
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Definition
- cytoplasmic NADH to mitochondrial NADH
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Term
| respiratory (acceptor) control |
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Definition
| ADP controls the rate of respiration |
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Term
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Definition
- results in heat instead of ATP
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
| observation that inhibitors of ATP synthase also lead to inhibition of the ETC |
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Definition
- if no ATP then no influx of protons into matrix dissipating gradient, therefore outside eventually becomes so charged that ETC can no longer pump against the gradient
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Term
| ATP synthase blocked by modification of a single side chain by dicycloheylcarbodiimide, what are the most likely targets of this reagent? |
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Definition
- it reacts w/ carboxyl groups making aspertate and glutamate side chains the likely targets
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Term
| how would you use site specific mutagenesis to determine if the residue is essential for proton conduction |
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Definition
- Asp 61 of subunit c in F0 subunit would be converted into asparagine by site specific mutagenesis eliminating proton conduction
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Term
| why mitochondria of muscle cells have more cristae than that of liver cells |
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Definition
- muscle cells have greater energy demands therefore require more ATP meaning more sites for oxidative phosphorylation calling for an increase in amount of cristae
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Term
| why the ETC ceases to operated upon exposing CAC to an inhibitor of ATP-ADP translocase. |
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Definition
- ADP and ATP cannot exchange b/t matrix and mitochondria, ATP synthase will halt d/t lack of substrate ADP, proton gradient will increase until ETC can no longer pump against it.
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Term
| use of proton-motive force other than synthesis of ATP |
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Definition
- ATP export from matrix, and phosphate import into matrix
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Term
| how inhibition of ATP-ADP translocase affects the CAC |
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Definition
- ADP can't enter matrix, ETC ceases to function d/t no energy acceptor NADH will build up in matrix inhibiting CAC enzymes
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Term
| how inhibition of ATP-ADP translocase affects the aerobic glycolysis |
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Definition
- glycolysis will stop aerobic function and switch to anaerobic so NADH can be reoxidized into NAD+ by lactate dehydrogenase
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Term
| lactic acidosis is most common sign of mitochondrial disorders b/c |
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Definition
- the means of generating ATP becomes anaerobic glycolysis leading to high levels of lactic acid in the blood
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Term
| use Chargaff's rule to calculate % of all bases in DNA that is 20% thymine |
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Definition
- T-20%, A-20%, G-30%, C-30%
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Term
| A stand of RNA is 20% U predict the % of remaining bases |
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Definition
- can't be predicted b/c single strand nucleic acids are not subject to base-pairing
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Term
| reason GC and AT are the only base pairs permissible in the double helix |
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Definition
- they only form stable H-bonds in this pairing, also 2 purines would be too large to fit inside the double helix while 2 prymidines would be too small to base pair together
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Term
| why heat denatures or melts DNA in solution |
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Definition
- the energy causes the chains to wiggle, disrupting the H bonds b/t base pairs & stacking forces are disrupted as well causing strands to seperate
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Term
| DNA chains in double helix have opposite polarity means |
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Definition
- one end of stand starts w/ a 5l -OH group while the other end is a free 3i -OH group, the 2 strands must run in opposite directions to form double helix therefore they have opposite polarity
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Term
| with weak forces holding the helix together why is it hard to disrupt |
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Definition
- individual H-bonds & stacking forces are weak but there are so many that they are strong accumulatively
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Term
| reason DNA double helix must be associated with cations, usually Mg2+ |
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Definition
- negatively charged phophoryl groups would be too much and cause repulsion so cations are needed to counter the charge
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Term
| 3 forms of a double helix |
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Definition
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Term
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Definition
- shorter, wider, and more dehydrated than B-DNA
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Term
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Definition
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Term
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Definition
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Term
| radioactive materials needed to tag DNA but not RNA |
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Definition
- tritiated thymine or tritritiated thymidine
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Term
| precursors to prepare DNA w/ backbone phophoryl atoms uniformly labeled 32P and position of the radioactive atoms |
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Definition
- dATP, dGTP, dCTP, TTP labeled w/ 32P in the innermost α phosphoryl atom
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Term
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Definition
- has RNA as it's genetic material. The RNA is catalyzed by reverse transcriptase to form DNA
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Term
| how is the flow of information in a retrovirus different |
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Definition
- RNA to DNA vs normal DNA to RNA
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Term
| Deoxynucleoside triphosphates |
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Definition
- activated precursor for DNA polymerase
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Term
| ribonucleoside triphosphate |
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Definition
- activated precursor for RNA polymerase
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Term
| direction of chain elongation for DNA and RNA polymerases |
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Definition
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Term
| template conservation for DNA and RNA polymerases |
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Definition
- DNA-semiconserved
- RNA-conserved
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Term
| need of a primer for DNA and RNA polymerases |
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Definition
- DNA-needs one
- RNA-doesnt' need one
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Term
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Definition
- encodes info that on translation yeilds a protein
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Term
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Definition
- catalytic component of ribosomes, molecular complexes that synthesize proteins
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Term
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Definition
- adaptor molecule, capable of binding amino acids & recognizing the corresponding codon, along with amino acids it is a substrate of ribosomes
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Term
| why is RNA readily hydrolyzed by alkali and DNA is not |
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Definition
- the 2l hydroxyl in RNA acts as an intramolecular nucleophile, in alkaline hydrolysis it forms a 2l to 3l cyclic intermediate
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Term
| degeneracy of genetic code |
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Definition
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Term
| biological benefit of degenerate genetic code |
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Definition
- a nucleotide change might yeild a synonym or a codon for an amino acid with similiar chemical properties
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Term
| relationship b/t number of amino acid codons and frequency of it's presence in proteins |
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Definition
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highly abundant amino acids have most codons, least abundant have least condons, allowing for variation in base composition and decreases the likelihood that a substitution will change the encoded amino acid
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